well it was probably pending and you got approved!
grats on the approval!
I personally HATE everything Bank of Amuirka has to offer, their only good card the Asiana credit card got severely nerfed late last year. But personally for a rule of thumb, I would say anything over 5k limit would be a prime card or a NSPL.
Id say they are PRIME but im a BofA fan so yeah lol
with your credit knowledge I have to shake my head at this comment =P
BofA is one of the "Big Four" banks along with Chase, Citi, and Wells Fargo. I would consider any of the cards in their main lineup to be prime. Most big banks also offer student cards and new to credit or rebuilder cards. These may target people with lower scores or thin files but keep in mind that they will grow with you over time. This is very different from subprime cards where that rarely or never happens.