Presence sensors, 100% battery, dropping out

I did the battery pack upgrade to my sensors, two AA batteries instead of the coin. Both sensors worked great for months.

Then a couple weeks ago they started ‘leaving’ even when present.
So I put in fresh batteries; both sensors are reporting 100% battery since I did that last week.

They are still dropping out.
This morning, one of them ‘left’ for six minutes and then returned… without changing location whatsoever. It is in the same place it always is when it’s in the house, and nothing in my network has changed during this time. In fact, that sensor is within 10 feet of a smart plug - zigbee/zwave repeater.

I have rebooted the hub. Problem is still occurring.
Anyone have any ideas what might be occurring?

a few things that come to mind…

Maybe some new WiFi interference? Did your hub change zigbee channels and is now using the same chunk of spectrum as your WiFi hub? Did you change WiFi channels? Neighbors set up a new/different WiFi network?

If both sensors are using the same repeater maybe the repeater isn’t repeating anymore?

Did you try rebuilding your zigbee mesh?

the wireless environment is always changing. You won’t see it happen.

Early on, I kept manually increasing my presence timeouts until it got to a max of 7 minutes - then all false-departures finally stopped. With only repeaters in the garage and elsewhere, with 1-2 minute timeout, false-departures had recurred 3-4 times a week. Also I setup modes to be presence-fault-tolerable.

Now I am not certain but it looks like ST automatically reduced my timeout at the hub level - I saw a value that looked like timeout, something like 2.08333 which I assume is in minutes . The presence debug statements from the log, appear to have more logic than just timeout delay.

Anyway - I would figure out how to increase timeout until false-departures stop.