Changed my slides today, and after about 30 minutes, the dates have been updated in OH.
But the serial stays empty. So the ‘change’ hasn’t been noticed.
Not a big deal of course, since I don’t see any reason why we would like to remember the serial. 
Ben,
Thanks for the info, can you upload a copy of the logs for the time the date of the slide updated.
This might help me identify the problem with the serial number.
Mick
Nevermind. Was an error on my side. Seems I forgot to add the [%s] to my item… 
And worse, I was to lazy to check the logs, else I would have noticed it. Sad how much you rely on the sitemap. Like everything will be handled automaticlly by the computer. It’s just not like in the commercials… 
log/events.log.7:2020-06-01 17:29:56.079 [vent.ItemStateChangedEvent] - BotjeVijver_slideexpires changed from 2020-06-02T11:39:15.000+0200 to 2020-07-01T17:27:15.000+0200
log/events.log.7:2020-06-01 17:29:56.079 [vent.ItemStateChangedEvent] - BotjeVijver_slideSerial changed from U71SU623PK8 to N34EV366KG4
log/events.log.7:2020-06-01 17:31:15.124 [vent.ItemStateChangedEvent] - BotjeAqua_slideexpires changed from 2020-06-02T11:39:58.000+0200 to 2020-07-01T17:26:43.000+0200
log/events.log.7:2020-06-01 17:31:15.125 [vent.ItemStateChangedEvent] - BotjeAqua_slideSerial changed from L27HS836MX2 to K17KC688EM1
With other words, this binding is working perfectly for me.
Thank you very much !!!
If I can do anything for you to test or so, let me know!
Excellent, glad you get it sorted.
Thanks for the feedback.
OpenHAB 2.5.6-2 includes the latest version of the Seneye binding, So no need to have a separate copy in the addons folder
For best results delete the current things and uninstall the current binding before upgrading to OpenHAB 2.5.6-2.
Then reinstall and configure.