My watch arrived yesterday and I've had issues connecting with WiFi. It may just be used error so will try to play with it a bit more today/tomorrow. When I test the WiFi connection on the watch via the phone it works fine. When I just select to connect to WiFi via the watch directly it fails to connect.
As a follow up. I deleted the wifi network from the watch, and reentered it via the watch rather than the phone. From an initial quick test it now seems to work and my activity was uploaded to Garmin Connect servers via wifi.