I got one last night..but my alert settings are probably different from yours. You might want to be more specific about what type of alert you didn't get?
I have noticed that they're a bit hit and miss. I am watching Cody's build, but only get an occasional notification in the bar at the top of the screen. Having said that, I never opt to get emails, get too many already.
Yesterday Ryan told us that recent updates to Garage Journal are impacting the database it shares with the Hamb. This might be related. I'd give it a little time.
I haven't been getting consistent thread alerts for 2-3 years now. I have yet to see or read what can be done about it.