I need an Android Beacon that advertises the current date and time

The app needs to be only broadcasting, not connecting. I have a lot of simple devices that have no battery backed clock. When they are switched on, I want them to get the current time using BLE from my phone so they can timestamp their data. Time can be approximate, to the minute, so transmission latency is no problem. J2000 epoch time is 4 bytes long so it would fit in the Major and Minor number fields of an iBeacon advertisement. There are probably good places to place the data in other type beacons as well.

Is there an AI2 extension for putting a few bytes of data into a BLE Advertisement?

Is there a simpler BLE way to do this rather than a Beacon Advertisement?

Is there already a phone app that does this?

I am using MIT App Inventor 2, Windows 10, Firefox

Thanks.