Thanks @simog72 but that's not what I said in the email to you earlier.
Sounds like wires are getting crossed and best for me to forward that email to you again and explain again.
But you can't upgrade from 2.x > 4.
Pulse 3 licenses could but not v2.
And Pulse 5 needs an upgrade license also.
So in most cases anytime there's a major 1.x upgrade, you'll need to buy an upgrade.
But the way we have it now, when you buy you get upgrades for 12 months. Should you wish to continue getting upgrades, you need to re-buy a 12 months extension. But if you choose not to, it's ok and your Pulse site will continue working.
I'll forward this to you in an email in case you don't see it here