My slack (desktop + mobile) has been down for the past 30~ mins.
Strangely I can still receive messages/alerts on my phone.
I imagine their infrastructure to send push notifications is decoupled from their infrastructure for chat services themselves.
It'd be interesting to know if they have a master switch to disable notifications in times like this where they aren't usable anwyay.
I wonder if this is because I haven't used the phone app in a few days, so I was already logged out, but you and others were still logged in?