UPDATED 12:45: We are still seeing issues with Microsoft systems, they are returning to normal however there are an incredible amount of backlogged emails that need processing by vendors (e.g. filters) and Microsoft themselves. As such, you should see emails arriving however they may not be in any particular order when they do arrive as systems retry delivery at various points not in a specific order often. Ultimately unless further update is announced over the weekend we would expect everything to be back to normal on Monday and caught up. Do note however if an item of email never arrives it could of timed out and the sender would need to resend the email.