I have noticed recently that my iPhone XR quickly flicks from WiFi to cellular and back to WiFi (taking around 1 second) when I wake it. Sometimes this happens after the device is locked for less than a minute. To the best of my knowledge I have not noticed it do this before and I am on iOS 13.5.
Is there a reason for this and is it a recent phenomenon others have experienced?
I have recently started using ProtonVPN and am aware that iOS disconnects this when the device sleeps, causing it to go to 4G until the VPN kicks back in (if it does). Having turned that off, though, I thought the WiFi would stay permanently connected as in the past, but it appears not. Even if the WiFi deliberately disconnects to save power, I never visibly saw it toggle between cellular and WiFi as much as I do now.
I have just received an iOS alert saying my device hasn’t been backed up in 2 weeks, which I’ve never had before. The device should be plugged in and on WiFi overnight, allowing it to back up.
So all in all, it seems to be a recent issue which the VPN seems to exacerbate. I’ve reset network settings, but to no avail. Is there anything that can be done or is this an iOS issue?
Update:
The WiFi network in question is my home network. I have a pretty standard, no-frills ISP-provided router (Plusnet). The network is set to auto join and has full signal everywhere in the home. My iPhone can pick up four or five other networks from neighbours. There's nothing really notable about the setup. It's generally reliable. I've not noticed this issue with any other devices.
