2019 DCSB 6MT major AUTO 'parking?' BRAKE issues, locking up from stand-still

Hoping others have experienced this and can provide some ideas.
Have done extensive searching and all threads seem to discuss issues of auto brake while in motion.

Started intermittently about a year ago (~33,000kms) and currently almost 100% of the time.
Want this simple to read so will try point form...

+ usually, following ignition, clutch in, put in first, clutch out slow can feel auto brake holding, so clutch back in to avoid stall

+ sometimes putting in reverse at this point will release auto brake and can proceed forward, other times still holds but will release on subsequent shift to first, other times some throttle helps by pushing into auto brake in either reverse or first

+ fairly confident this has never occured while driving or while at a red light or stop sign, yet frequently happens when pulled over to side of road or into parking space to stop for a minute, auto brake holds again when putting in first, regardless if restart the truck or not

+ fairly confident this never happens in my underground parking at home, no clue if it's due to longer duration overnight or the environment

+ disabling PCS (permanently via Techstream) does not have any influence on this behavior

+ parked uphill on a driveway, after ignition with brake pedal down, released brake pedal and immediately felt 'hill assist' engage as expected, wanted to reverse so waited the two seconds and hill assist released, truck started to roll back for split second then heard loud click and good old auto brake clamped down holding the position until I put in first and reverse again to release it

+ I assume this is parking related because it only happens from a complete stop and the brake light does not come on

+ does not matter if parking brake lever is pulled up and released or not used at all so it feels like a mad sensor rather than anything mechanical

+ dealer wanted $340CAD to disable PCS and otherwise said it's my fault because big tires and lift even though same setup had no issues for over 30,000kms


Happy to elaborate if anything not clear. Thanks for reading!

 

very weird. Sounds either electrical or like your brakes might be rusting shut every once in a while? But even then you'd think it wouldn't happen so quickly when you park for just a minute

why do they always blame the tires...

 

Very bizarre indeed. Highly unlikely anything is rusting. Feels like very intentional actuation with that loud click.
Speaking of clicks, it does sound similar to the 4x4 engagement/disengagement click, and I do have the 2Low bypass and never had any issues with its function.
Though I can't fathom how that can be related to auto parking brake.