"There has been a patch that you need to update to"

Apparently this is a bug that happens every other league so just pointing it out again.
My game validates for ~5min min on launch and then hits me with the message :there has been a patch that you need to update to.
Im on Canada east and using steam.

Did you manage to fix it? I have the same problem. I have the latest 3.28.0h patch and see the same behaviour as your client in Steam.

Edit: I managed to fix it by switching servers. Moved from Amsterdam to London. Suggests to me that some of the servers need to be patched!

I have the same problem.

Changing servers doesnt help me, I can play the game if I hit log in again after the message.

Reinstalling the game did not help either.

And steam validates files every single time.