Transition to Sophos Connect from the SSL VPN client

I received the email below from one of my long-time customers - an adjunct prof of computers at Oklahoma University, so he's very knowledgeable and not easily flummoxed.  I've not done this yet, does anyone have answers to his questions?

Cheers - Bob

-------- Original message --------

Bob,

THANKS for the link.

And, it's totally obvious that to set up Sophos Connect on a Windows 11 machine, you'd pick the Linux, MacOS X, BSD, or Solaris option<G>.

However, I worked through all of this, and the new (test) computer won't connect because the key length is too small.

Is this something that when I change the server key length, all of my old users can't connect anymore?

Or, does it just use these to build the profiles, and then I can swap 'em out one at a time?