I'd like to upgrade from basic to pro. On the registration screen, I assumed I would enter the existing information (i.e. account name, display name, user name, etc). When I enter the account name for the existing basic subscription, a red button saying "TAKEN" pops up. Do I just ignore what looks like an error and plow ahead with the (re)registration? I know this seems obvious and I'm 99.9% sure the answer is to plow ahead, but want to be 100% sure as I've put quite a bit of effort into BH and have gigs coming up so can't afford any hiccups. Thanks.
You don't have to register again. Just go to the Account > Billing page and select a Pro option and make a payment at the new price.
Glad I asked. Thanks, Arlo!