Yes, the DC ticket or confirmation (I forget). Your confirmation e-mail should state something about using it as your ticket/parking pass if you go to the other parks first. You can just go to the turnstiles and scan in as though it is a normal SW/BG ticket.
Third time! That's awesome. We loved DC. Yes, the paper printout of your ticket. Usually, it's an 8.5 x 11 paper with a bar code and lots of fine print. You shouldn't have to go to guest services. It should say "this is your ticket. go directly to turnstiles/some letter." In fact, on day two we tried to go to guest services to exchange our paper printouts for the normal ticket cards. They couldn't do it. We folded ours and kept them in a ziplock in the backpack so they wouldn't get wet. Scan one to enter the parking lot, then everyone scans to get in, and then pack them in the ziplock in the backpack until the next day. It wasn't a huge hassle, just a minor thing I didn't think about until we were there. DC uses the same paper ticket to check you in, then gives you the lanyard you're familiar with that can be used at the parking lot at park entrances for the remainder of your two weeks. I'm not sure if DC can check you in early, the lanyard has your dolphin swim time on it, not sure if that can be assigned earlier than the day of. They may be able to give you plastic ticket cards without the swim time for parks use and swap them on your official DC check-in morning. It's just two days though. Instead of spending my morning trying that, I would just use the papers and enjoy low morning crowds at Sea World or Aquatic.
On my last trip the paper tickets worked for Seaworld but I had to turn in my paper ticket at guest services for a little card at BG that then worked for the 14 days. Paper tickets will work for parking.
I realize you got other replies, but I still wanted to get back to you. We really liked BG Tampa. We had our nine-year-old and friends with a 21-year-old met us at the park. The coasters are fantastic! I read a few tips about how to best visit the park and they were spot on. We were there on a Friday and Saturday during spring break, early arrival was crucial. Parking got so hectic for our friends who arrived shortly after opening. We were there at least an hour before park opening each morning. Did some big rides first thing, then a show, and rides with shorter lines. The app isn't as helpful at WDW for things like ride wait times, so reading up on what to ride first was important for a good day for the group. The drive on Saturday late afternoon wasn't pretty. I knew it would take an hour and a half or two hours with just typical traffic that time of day and it did. Some lovely stop and go slow downs. No accidents. Just congestion. If we skipped BG that morning it would have been a shorter drive, but we wanted to be in the park. The "kids" watched movies and it passed in no time. We would absolutely do it again, either starting or ending with BG because that DC combo ticket is such a great deal!
