I normally just troll here, but I figured I would finally sign up and share a little.
So, the MTA 33 (San Antonio) includes Gillespie cty, which I think is in BTA 401. They are A block, G block, SMR and a whole host of band 41 spectrum. Austin is somewhat goofy as a market (as far as sprint markets go with spectrum), some parts Sprint owns C block, which butts up against G block. AUS is included in the DFW MTA, but there are a TON of BTAs in north Texas, so spectrum can vary from cty to cty. Some states have pretty much the same spectrum ownership in every BTA. For example, almost all of Florida is a 7 carrier market (in terms of legacy CDMA spectrum). However, around Orlando there's a little more spectrum to spread around. With all of that drivel, I could have easily just said that Gillespie is in the San Antonio MTA, but spectrum holdings are normally related to BTA. A couple maps below that might be fun for some of you other geeks.
As far as guard band goes, there are some differences in opinion. They say if you butt TDD and FDD next to each other you need a full 5Mhz, and two consecutive (and equally timed) carriers need no guard band. That second statement makes me laugh, because if you own those two slots, then you just up the size of your carrier, right? For example, if C block opens up in Austin, the plan should be to roll into a 10Mhz carrier rather than having a second 5Mhz carrier, right? One big carrier is more efficient than two 5Mhz carriers.
As far as guard bands go, typically, a carrier will own a full block of PCS band. The frequency planning should take into consideration the spread needed. However, the carriers usually have an agreement to not use the bottom carrier in a block in order to keep it clean for the other guys. For example, in the B block markets the carriers on CDMA will start with burning the 400 carrier, and FA1 will be 425. The last carrier that will be used is 675. If you're A block, you don't use "0", you start at 25 and work your way up.
As far as the 15x15 reference goes, it's best to term the current usable spectrum as 5+5+5 FDD. They are non-contiguous and one of them is out of band. They won't Aggregate at the moment, so they aren't mashed together to allow for a single big carrier.