I’ve been running version 2.4.8 of the app on both my iPhone and an iPad and I’m noting frequent and oddly regular cadence and power dropouts on screen and in the resulting data.
iPad Air 2 is running 14.4.1 and the iPhone 11 is running 15.0.2
It’s ocurring in both ERG and slope mode. I’m paired via BT to just my Wahoo HR strap and the Neo2T trainer, which is on the latest firmware. Here’s a screenshot of what I’m seeing in Trainingpeaks.