Well what do you need? an ATP?
They do that in a 4 day course, I've seen a few guys do it, one of them did it in 4 days, the others, since it was an out station and not in perfect weather Florida, took 5 days. WX always comes into play.
You get one instructor to be totally yours all day for four days, or however long it takes.
Everything is really custom fit around your schedule. So if you cannot do it in four consecutive days, then you don't.
http://www.atpflightschool.com/programs/certificates/atp/atp_and_written.html
The simulators are great for getting the flows down in the Seminole. I do not believe you are really limited to time in those. Just when they are available, beyond what the program included, which is quite a bit.
They will send you the ATP Piper Seminole Training Supplement before you go, you will really want to know that thing from front to back cover. It's small sized like a POH, and not nearly that thick.
I'm sure theres tons of guys who can comment about it on here. It's a lot of studying in a short amount of time. Eat Sleep Airplanes for 4 days, and the few days you take to learn the supplement before you arrive and all the other materials.