My S90D is still on 2018.48.12.1, and I have the TACC / AP2 issue mentioned above - every time AP2 is disabled, the TACC speed resets to the current speed, instead of remaining at the AP2 speed set previously....very annoying. When I'm in traffic, if AP2 disengages, as things clear up I realize my car isn't accelerating up to speed because it reset to 8 mph, or 14 mph, or whatever crawl speed traffic was at...frustrating and IMO possibly dangerous as it distracts the driver thinking something isn't working correctly....
Short answer - not a problem created in 2018.50.6