In my opinion, taking 2-5 days to change your MAC Address is a load of BS.
All they have to do is type your new MAC Address into their system as you read it to them. The only reason they are saying 2-5 days is because they're lazy.
I'd call them and complain to the manager, that is just laziness.
Damn, give me the #, I need to call and chew them out again... Friggin @home, I hate 'em.