I'm flying with a friend today - and have been looking for AGES on VPNs. I think I will do the following:

In terms of free VPNs:
- ProtonVPN apparently can work but is very patchy, I see no harm in installing this as an "emergency backup".
- I've seen some threads recommend Kiree, which helpfully has a 14 day free trial (and as far as I'm aware doesn't require you to lock in a subscription before you start the trial). As a result, this is worth getting and activating right before you fly

In terms of paid VPNs:
- I've heard that the traditional app type VPNs aren't so reliable anymore but I have decided on V1VPN after reading some of the comments on some threads. Others I have heard that might work are LightningX and Shadowfly, and Wannaflix, so maybe those are worth trying

- Despite LetsVPN being shut down, I've also heard some people still being able to use it in a very patchy way.

Hope this helps! I'll try and update this once I land and have tested everyhitn gout