I discovered today that my Strava connection had been turned off in the companion app and had to restore it. Zwift companion app on android 3.44.1 (1509). My ride on Thursday uploaded as usual, took Friday off, and today (Saturday) nothing uploaded.
One other person I know of had the same thing happen, anyone else?
Strava’s website also seems to be struggling today…
I’d wait for Strava to come back up again… my warm up ride from before midday went up OK to Strava, My Medio Fondo ~3 hours later hasn’t. 
Strike that… my Fondo ride is there, but the Strava website is still broken for me.
Strava off here (Austria), no problems yesterday.
after many many tries I got them to upload… first world problems…
I had to reconnect recently, looked like it had gone again today, but officially I’m still connected it’s just the ride hasn’t made it.
I’ve done a manual upload of the FIT file, but will delete if the Zwift one comes through.
It looks like Strava is slowly starting to come back up again. That cliff edge just after 15:00… 
Mine was not connected, had to click the check mark today and log into strava as if I never had them linked.
Not Zwift related but Strava website is struggling today.