Alert when item in a group has not been updated for x hours?

Currently I have a few sensors and I have individual rules for each to populate a separate LastUpdated item for each item.

What I’m looking for is a way to just put all my sensors into a special “LastUpdated” group and then get notified by some sort of alert when one of those items has not been updated after x hours.

Can anyone comment if this is possible?

No one got any bright ideas on this?

Perhaps this might be somewhere to start?

You’d have to extend the rule to compare the filtered lastUpdate items with a current DateTime item (NTP?) Maybe something from here would help with that part of the rule.

In addition to @pahansen’s links, I’ll include:

Pay particular attention to the Expire Binding version near the bottom of the first post.