A positive development? 515/991 TSN5K has been broadcasting the CFL game without issue, no frozen picture, no XRE error!
All other existing issues remain. e.g. 507/997 SN4K is showing the SNO (HD-only) feed right now of the Jays home game, and it's broadcasting it at a noticeably slower frame rate than the other SN channels.
With the shifting of programming around today with Rogers Cup, the Jays game was moved to SN1, which meant that for the first time in some time, the home Jays broadcast was available on 509/996 SN14K. As you can see, this is broadcasting the correct 4K feed:
So the 4K is definitely capable on the SN feeds in Ottawa, it's just a matter of getting the right 4K feed for 507/997 SN4K.