ERG workout issue when stopped pedaling midride and continue

I did yesterday an ERG workout (PC, via ANT+ , Tacx Neo1) and i was middle in a 5min 210w endurance block, i wanted to do a very short stop to doing an auto-zeroing on my Power2Max NG (for dual recording, it is paired to my head unit) , so the ERG mode was temporary disabled , after 4-5secs coasting i was continouning to pedal as before, the ERG was enabled again (as Zwift wrote) but not in ERG mode, in SIM mode (i checked the log file and found this line to prove it: [13:48:47] FE-C SIM GRADE 0.010 ) and this SIM mode was active till the next block (apprx 1.5min, many same SIM commands what i wrote before, luckily i programmed 6x5min instead of 1x30min) where the trainer got the next message to switch to real ERG mode and working on the target 210w . In the past this wasnt the case, if i did such a coasting during an ERG workout, the trainer continued on the same power target where i stopped, didnt switched/(remained in) to SIM mode till the next block. And it is not only a single case, one of my friend reported our Zwift forum that he had similar issue with an Elite Drivo. My question is why did You change this kind of behavior? Is it only ANT+ issue or via BT also?