My recent data points...

Over the last week I've had 3 different flights. 1 booked via TA (booked pre-migration), not upgraded. 2 booked with flight pass (post migration), both upgraded. I wasn't able to use the app to OLCI any of the 3 flights - I kept getting an error that the PNR couldn't be located. 1 of the flights (I can't remember which one) I tried checking in using the website but got an error message too.

There was no issue checking in at the airport for any of these.

One of my flights I got the the airport a bit early and saw that the previous YVR-YEG was delayed. I was able to standby for the earlier flight. Agent printed off a SBY BP in addition to the one for my confirmed flight and off to the gate I went. Total time to check-in with agent (including getting put on standby for the earlier flight) was probably only 1-2 minutes. My booked flight had been upgraded to J - I found it interesting that my SBY BP was for as well (I thought they might have put me on SBY for Y cabin but they didn't).