Good day!
Hi!
Just found this:
To turn updates on or off, follow these steps:
1.Open Google Play.
2.Tap the hamburger icon (three horizontal lines) on the top-left.
3.Tap Settings.
4 .Tap Auto-update apps.
To disable automatic app updates, select Do not auto-update apps.
But I believe, there's an option there to notify you first before updating. So you may be still up-to-date if there's an update for other apps while ignoring to update psiphon.
(As its updates come directly from GPlay, I do still believe).