Some users stated that they had to go check "Advanced options" and it was offered as Optional update.
I check that always, and no, it's not there either.
Same issue happened just before 22631.3668 became available and the problem fixed itself in a day or so. This time, it is persisting, even with all the complaints. Chatted with Microsoft help, she couldn't help me either.
Going by the usual schedule, the public release should be available in a couple of weeks. For those regular updates, it seems like the RP channel and the public release coincide, for at least two days to a week or so. I'd expect MS to fix this problem by then?
I wish someone from MS would speak up, already. Why keep this such a secret?