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New (home) charging behaviour?

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I have a 2017 MX 100D. It’s been upgraded to AP3 and MCU 2. I charge at home with a Gen 1 Wall Connector provided 240V/32A.

I’ve been noticing a change to the charging behaviour lately. I can hear the relay in the Wall Connector actuate pretty much throughout the house. Up until recently, the car would be set to charge at night, and it would begin charging at the scheduled time. Once it was charged, it would stop and wouldn’t charge again until the next night at whatever time I had set.

Recently, it seems it’s been charging at night, and then “topping up” throughout the day - I can hear the relay clunking on and off fairly regularly. The change seemed to come with the firmware update that added “Scheduled Departure”. This is undesirable as we have time-of-use rates and I’d rather accept whatever range decrease happens over the course of the day than be continually topping it off.

I’ve tried unlocking the charging port, but if the cable isn’t unplugged, it will just carry on. As I sit typing this, I just heard the Connector relay and in the app, it showed “Starting to charge”. Obviously, in this circumstance I could cancel it from the app, but I presume it will just happen again in a little while.

The only option I can think of is to reset the desired charge level in the app to something well below the 70% I normally charge to, so that it won’t feel the need to turn the charger on. That is, obviously, undesirable as it will eventually bite me in the @ss someday when I forget to reset it and wake up in the morning with an uncharged battery.

Any suggestions on options I might have missed appreciated.
Try going into your settings in the car and turning the option for scheduled departure on and off. I have a hazy recollection of some other threads where someone was asking about weird charging behavior after a firmware update that did something with scheduled departure. Cycling the car's settings seemed to fix the issue for some of them. The hypothesis was that in the process of updating a discrepancy between settings was accidentally induced.
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We saw this same behavior in our 2017 S100D that is set to scheduled charging. We thought that maybe the 12V battery was going out. Tesla mobile came out and checked it and didn't see any problems. We got a software update and rebooted and it went away for a couple months but it seems to have returned. I will try rebooting it again to see if that fixes it.
My 2020 S is doing much the same thing after 2021.4.12.
I leave it plugged in with 70% set: every 10-15 minutes it will charge for a couple of minutes then stop. Sometimes the instrument display lights up, sometimes not.
I'm wondering if there is no allowance for hysteresis - I would expect the car to allow the SOC to go well below 70% then charge up to say 71% before cutting out so as not to constantly cycle like this?