Battery Woes

Hi All

I have a 2016 Ford Transit 250 that's had some problems with the battery dying, and looking for some input to see if I'm headed down the right path to figuring it out and fixing it. I'll provide all the info I can below but feel free to ask anything else.

We use the van sporadically, so sometimes it sits for longer periods like a month without being driven. Noticed the battery struggling after long periods of sitting a while back, and just started jumping it when this happened, but it got worse over time. I eventually replaced the battery, but this didn't solve the problem.

Getting more into the weeds, I again replaced the battery (under warranty after the newish one died again), and did some basic checks: With brand new battery and multimeter in line, it draws 0.160 amps at rest, which is higher than the expected 0.050-0.085 range.

I checked the codes and there is a P2610 code for "ECM/PCM Engine Off Timer Performance", which seems to indicate a problem with the engine or passenger control modules. Tried unplugging the entire engine fuse box but that didn't reduce the baseline current draw.

I guess at this point I need to start taking apart the dashboard to get to the passenger and body fuse boxes to see if any of those reduce the baseline current draw, but before I do so, does this seem like the logical next step? Has anyone had similar problems with a transit that might point me in a more specific direction?

Thanks in advance for the help!