Erratic ERG wattage in workouts

I posted this in known issues, but thinking I should have posted it here (sorry, just getting to know my way around the forums) - please delete whichever post is in the wrong place

ERG targets often do not update in sequence with the workout description - e.g. with an FTP of 200, a couple of workouts are supposed to be 105W and 145W segments, but in 4/5 of the workouts I’ve done, the changes seem random compared to the plan.

In my last workout the description was just wrong too - the workout plan was for a 5 minute gradual warmdown, the text on the screen that appeared at the start of the warm down said that it was a 10 minute gradual warmdown, but the Wattage only began to drop down after 3 minutes 40 seconds…
This almost seemed to me that the ERG connection was working fine, but that the workout programme itself was not set up the same as the screen description?

One workout was an exact match between on screen and ERG Wattage changes, but only one.

This was Windows App over Bluetooth, to a Kickr Core, no Zwift Companion app running

I should add that every ride I have done in SIM mode has worked exactly as I would hope & expect - it’s only ERG mode that has issues.

I had exactly the same issue again today

ERG is actually working (pedalling faster makes the resistance lighter so the wattage output doesn’t change) and vice versa; the problem is exactly as described - the target wattage is out of sync with the workout.

Another give away is in the last two workouts I’ve done, the final block was a 5-minute warmdown, but, disregarding the fact that the wattage was set wrong for the warmdown, the on screen pop up text read ‘now we’re going to do a 10 minute gradual warmdown’

ERG is actually working, it’s either that the coding for the workouts is wrong so that the Wattage changes at the wrong points, or the workouts have changed and they didn’t correct the coding to match

Windows App, BLE, Kickr Core and Kicr Climb (although I lock the Climb for workouts so that it stays at 0%)

I’m experiencing the exact same issue on Windows 10 with my devices connected directly to Zwift.

Sim mode works fine but as soon as I switch to ERG mode, Zwift doesn’t send the trainer regular ERG watt target updates and very soon the ERG info getting sent to the trainer is several intervals (and minutes) old.

Pairing devices to the Zwift Companion app seems to solve (workaround) the issue.

I just did the Wk2 D1 Foundation workout of the 6 week FTP Builder, and it worked perfectly. No issues at all.

There were four differences, one of which I think is critical:
I was using a Wahoo HR monitor instead of my unreliable iFit one
There were considerably fewer Zwifters online than in my afternoon/evening rides
I didn’t need to stop to adjust settings, answer the door, etc

But the critical factor IMO is that everything matched up - the description of what was to come matched what did come, and (what’s becoming the telltale sign for me) the 5 minute cool down on the schedule was matched by the central text describing a 5 minute cooldown.

I’m becoming convinced that the only problem is that some workouts are programmed incorrectly, as evidenced by the fact that in the three last workouts that have failed, the blocks in the schedule did not match what was in the centre of the screen.

In the two workouts that have worked, everything has matched

This was with Windows 10 direct connection, Wahoo Kickr Core & HR monitor, Kickr Climb connected but obviously locked as in ERG mode. No companion app open.

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