OK so here are the two logs, which show the temperature rising, and the rule just ignoring it.
From openhab.log:
2021-03-17 12:57:52.821 [DEBUG] [onoff.internal.connections.Websocket] - Pong Response received
2021-03-17 12:57:59.590 [DEBUG] [noff.internal.handler.HandlerAccount] - Sonoff Connection Check Running
2021-03-17 12:57:59.613 [DEBUG] [ding.sonoff.internal.connections.Api] - Api Discovery Request:{"appid":"oeVkj2lYFGnJu5XUtWisfW4utiN4u9Mq","nonce":"U7YFa8vQ","ts":1616000279613,"version":8}
2021-03-17 12:58:52.719 [DEBUG] [onoff.internal.connections.Websocket] - Websocket Sending Message:ping
2021-03-17 12:58:52.840 [DEBUG] [onoff.internal.connections.Websocket] - Pong Response received
2021-03-17 12:58:59.592 [DEBUG] [noff.internal.handler.HandlerAccount] - Sonoff Connection Check Running
2021-03-17 12:58:59.617 [DEBUG] [ding.sonoff.internal.connections.Api] - Api Discovery Request:{"appid":"oeVkj2lYFGnJu5XUtWisfW4utiN4u9Mq","nonce":"mw1HR3uO","ts":1616000339617,"version":8}
2021-03-17 12:59:39.616 [DEBUG] [onoff.internal.helpers.MessageSystem] - Websocket received message: {"action":"update","deviceid":"10005b9606","apikey":"53c83924-c0eb-4ffa-a289-190c37aae625","userAgent":"device","params":{"currentHumidity":"unavailable","currentTemperature":"16.8"},"from":"device"}
2021-03-17 12:59:49.613 [DEBUG] [onoff.internal.helpers.MessageSystem] - Websocket received message: {"action":"update","deviceid":"10005b9606","apikey":"53c83924-c0eb-4ffa-a289-190c37aae625","userAgent":"device","params":{"currentHumidity":"unavailable","currentTemperature":"18.8"},"from":"device"}
2021-03-17 12:59:52.734 [DEBUG] [onoff.internal.connections.Websocket] - Websocket Sending Message:ping
2021-03-17 12:59:52.845 [DEBUG] [onoff.internal.connections.Websocket] - Pong Response received
2021-03-17 12:59:59.593 [DEBUG] [noff.internal.handler.HandlerAccount] - Sonoff Connection Check Running
2021-03-17 12:59:59.621 [DEBUG] [ding.sonoff.internal.connections.Api] - Api Discovery Request:{"appid":"oeVkj2lYFGnJu5XUtWisfW4utiN4u9Mq","nonce":"XdSfFpAc","ts":1616000399621,"version":8}
2021-03-17 12:59:59.645 [DEBUG] [onoff.internal.helpers.MessageSystem] - Websocket received message: {"action":"update","deviceid":"10005b9606","apikey":"53c83924-c0eb-4ffa-a289-190c37aae625","userAgent":"device","params":{"currentHumidity":"unavailable","currentTemperature":"21.1"},"from":"device"}
2021-03-17 13:00:09.643 [DEBUG] [onoff.internal.helpers.MessageSystem] - Websocket received message: {"action":"update","deviceid":"10005b9606","apikey":"53c83924-c0eb-4ffa-a289-190c37aae625","userAgent":"device","params":{"currentHumidity":"unavailable","currentTemperature":"23.5"},"from":"device"}
2021-03-17 13:00:19.643 [DEBUG] [onoff.internal.helpers.MessageSystem] - Websocket received message: {"action":"update","deviceid":"10005b9606","apikey":"53c83924-c0eb-4ffa-a289-190c37aae625","userAgent":"device","params":{"currentHumidity":"unavailable","currentTemperature":"26.0"},"from":"device"}
2021-03-17 13:00:29.656 [DEBUG] [onoff.internal.helpers.MessageSystem] - Websocket received message: {"action":"update","deviceid":"10005b9606","apikey":"53c83924-c0eb-4ffa-a289-190c37aae625","userAgent":"device","params":{"currentHumidity":"unavailable","currentTemperature":"28.4"},"from":"device"}
2021-03-17 13:00:39.669 [DEBUG] [onoff.internal.helpers.MessageSystem] - Websocket received message: {"action":"update","deviceid":"10005b9606","apikey":"53c83924-c0eb-4ffa-a289-190c37aae625","userAgent":"device","params":{"currentHumidity":"unavailable","currentTemperature":"30.6"},"from":"device"}
2021-03-17 13:00:49.686 [DEBUG] [onoff.internal.helpers.MessageSystem] - Websocket received message: {"action":"update","deviceid":"10005b9606","apikey":"53c83924-c0eb-4ffa-a289-190c37aae625","userAgent":"device","params":{"currentHumidity":"unavailable","currentTemperature":"32.6"},"from":"device"}
2021-03-17 13:00:52.746 [DEBUG] [onoff.internal.connections.Websocket] - Websocket Sending Message:ping
2021-03-17 13:00:52.861 [DEBUG] [onoff.internal.connections.Websocket] - Pong Response received
2021-03-17 13:00:59.595 [DEBUG] [noff.internal.handler.HandlerAccount] - Sonoff Connection Check Running
2021-03-17 13:00:59.624 [DEBUG] [ding.sonoff.internal.connections.Api] - Api Discovery Request:{"appid":"oeVkj2lYFGnJu5XUtWisfW4utiN4u9Mq","nonce":"zlVx5wP3","ts":1616000459624,"version":8}
2021-03-17 13:01:19.720 [DEBUG] [onoff.internal.helpers.MessageSystem] - Websocket received message: {"action":"update","deviceid":"10005b9606","apikey":"53c83924-c0eb-4ffa-a289-190c37aae625","userAgent":"device","params":{"currentHumidity":"unavailable","currentTemperature":"31.9"},"from":"device"}
And From Events.log:
2021-03-17 12:59:27.393 [INFO ] [penhab.event.ItemStatePredictedEvent] - Item 'BackStairwellLightSwitch_Switch' predicted to become OFF
2021-03-17 12:59:27.400 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'BackStairwellLightSwitch_Switch' changed from ON to OFF
2021-03-17 12:59:39.685 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'DryerSonoff_Temperature' changed from 15.6 to 16.8
2021-03-17 12:59:39.687 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'Sonoff1_Temperature' changed from 15.6 to 16.8
2021-03-17 12:59:42.758 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeteramps' changed from -62.403 to -21.575
2021-03-17 12:59:42.801 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeterwatts' changed from -7615.47 to -2432.703
2021-03-17 12:59:49.623 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'DryerSonoff_Temperature' changed from 16.8 to 18.8
2021-03-17 12:59:49.627 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'Sonoff1_Temperature' changed from 16.8 to 18.8
2021-03-17 12:59:59.654 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'DryerSonoff_Temperature' changed from 18.8 to 21.1
2021-03-17 12:59:59.656 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'Sonoff1_Temperature' changed from 18.8 to 21.1
2021-03-17 13:00:02.758 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeteramps' changed from -21.575 to -22.468
2021-03-17 13:00:02.807 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeterwatts' changed from -2432.703 to -2566.359
2021-03-17 13:00:09.707 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'DryerSonoff_Temperature' changed from 21.1 to 23.5
2021-03-17 13:00:09.709 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'Sonoff1_Temperature' changed from 21.1 to 23.5
2021-03-17 13:00:18.918 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'ZWaveNode008WAPIRZ1PIRMotionDetector_BinarySensor' changed from ON to OFF
2021-03-17 13:00:18.940 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'ZWaveNode008WAPIRZ1PIRMotionDetector_MotionAlarm' changed from ON to OFF
2021-03-17 13:00:19.653 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'DryerSonoff_Temperature' changed from 23.5 to 26.0
2021-03-17 13:00:19.655 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'Sonoff1_Temperature' changed from 23.5 to 26.0
2021-03-17 13:00:22.759 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeteramps' changed from -22.468 to -22.886
2021-03-17 13:00:22.800 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeterwatts' changed from -2566.359 to -2614.536
2021-03-17 13:00:29.667 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'DryerSonoff_Temperature' changed from 26.0 to 28.4
2021-03-17 13:00:29.669 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'Sonoff1_Temperature' changed from 26.0 to 28.4
2021-03-17 13:00:39.758 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'DryerSonoff_Temperature' changed from 28.4 to 30.6
2021-03-17 13:00:39.783 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'Sonoff1_Temperature' changed from 28.4 to 30.6
2021-03-17 13:00:42.758 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeteramps' changed from -22.886 to -20.566
2021-03-17 13:00:42.799 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeterwatts' changed from -2614.536 to -2200.302
2021-03-17 13:00:49.697 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'DryerSonoff_Temperature' changed from 30.6 to 32.6
2021-03-17 13:00:49.699 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'Sonoff1_Temperature' changed from 30.6 to 32.6
2021-03-17 13:01:02.758 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeteramps' changed from -20.566 to -62.201
2021-03-17 13:01:02.799 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeterwatts' changed from -2200.302 to -7612.718
2021-03-17 13:01:19.803 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'DryerSonoff_Temperature' changed from 32.6 to 31.9
2021-03-17 13:01:19.827 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'Sonoff1_Temperature' changed from 32.6 to 31.9
2021-03-17 13:01:22.758 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeteramps' changed from -62.201 to -62.676
2021-03-17 13:01:22.800 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'HomeEnergyMeterGen5_Electricmeterwatts' changed from -7612.718 to -7685.053
Any thoughts?