Hey folks a bit late in responding to this but thanks for the reports about issues with mission rewards. It's something we've been looking into the last couple days. No fix yet, but we're comparing issues on PBE and some tests internally, since this is something we want to make sure is fixed before we take 11.16 to Live servers.
From our findings so far we aren't finding any evidence that rewards aren't being issued at all, just that in many cases they're very slow. 10+ minutes seems common, and an hour+ is less frequent but definitely there.