Being banned/Name change question

Its been a month since my character was falsely banned and now the restriction is over.
I sent another ticket about the incident but they have yet to reply.

My question concerns the threads I've read where banned characters (no matter the reason)
could not world change or get a name change.

Is this true about the name change even though you have the name in the server your characters
were banned?

Also, is it possible to still contest the ban after it has passed for you to be able to get a world/name change?