The log file that you sent covers the period from 23:55 to 01:46, this doesn't cover when the set pier side error that you reported happened. It look as if the previous log file may be the one that is needed
However I would expect that there will be an error. The StarSense HC will not do a pier flip before the meridian.
You must set the meridian flip to after the mount has crossed the meridian.
One thing that would help is if SGP were to keep trying when a meridian flip fails. What I'm thinking of is the mount tries to do a meridian flip, if it fails it takes the next image anyway, then, when it is finished, tries again.
It keeps trying to flip until the mount indicates that it has succeeded. This would handle the situation where the mount isn't quite ready to flip when it's commanded.
The StarSense has been intensely frustrating for me. It's got such promise - no need to do an alignment by hand - but Celestron's implementation of it seems to me to be half hearted. There are all sorts of things that the normal HC will do but the SS HC won't do, this problem with Side of Pier is one, their failure to implement their sync command correctly is another. I have absolutely no confidence that they will ever do anything about these.
Chris R