Lock screen notifications getting stuck?

[anon(9072051)]

Anyone else noticing this? It's happening all the time with Gmail on my 6P, which also seems to be the only app to light up my black lock screen with a notification. Instead of getting a notification related to the text of a new email , say from XDA, when the new email arrives, the display lights up with a notification about an email that may have arrived 6 to 10 emails earlier, say some new sales pitch from Paypal, which is the one that has repeated at least 5X this morning.

I'm wondering if I need to do something in settings, or if it's just a beta bug, or if notifications in O are gonna be set to prioritize advertising emails.