10.9.6.2 uses an old version of the Logincode for generation.
The only theory I can come up with here is that Gameforge is still allowing the "old", longer codes (without "io:" at the start) to be used, like they did sometimes in the past.
However, surely this support will be dropped in the future at some point and then you can no longer login with it. It's on your own risk.
But what you are trying to say is that you can also login with blocked IPs using the old Logincodes? That would be surprising.