I believe is true for all PT school that you can apply while taking pre reqs. Usually you apply in fall or beginning of spring for the following fall so it is common to still have prereqs to be taken. For the GRE I would think only you know the time you need because we are all different. However, you should really plan to take it well in advance. First, results are avilabe after 15 days, Also, a lot of people take it twice in order to obtain better scores and you can only take it once a month, and is by appointment so availability is limited in some areas, so yeah you should really plan ahead. Also, if you got/get financial aid you can obtain a letter so you can get a discount when registerin for the GRE. It takes like a month too, I found out late so I couldn't take advantage of it =(
I don't know if you work as an ide now or plan to, that's good exposure, and I learned a lot just volunteering. I also think that for interview purposes, it helps to have a extra curricular activity. I do ballet and I was able to incorporate that in my interview. It helps me relax AND gives you knowledge about muscles and movement, and also check out the APTA website once in a while so you can check out what's going on in PT
Most schools are participating in a Physical Therapy Centralized Application Service (PTCAS), so you will be applying through this service. You can find out more about it at the American Physical Therapy Associations (APTA) website. Schools have different application deadlines but through this service you will be able to complete one application and submit it to multiple programs. Some of the things PTCAS requires are essays (sometimes you have to submit multiple essays for schools that require specific responses), letters of reference (schools have different requirements), documentation of PT observation/volunteer hours (almost every school requires at the very minimum 40 hours, and many require it be from multiple settings), transcripts received by PTCAS from every college attended, resume of non-pt work experience...and other stuff but that is a lot of it. As you can see there is alot of work in applying, especially because every school is a little different in what is required. It is good that you are thinking about it now and starting to prepare.
Well it depends on the school. For example in St Augustine they allow you to apply even if you don't have the results yet. I called and they told me to just add a note saying my results were not ready. You just have to make sure they get it. So I will just ask them. I don't think it really matters where you get your hours really. At least that's my impression. However, I think it would look awsome if you have more/different experience(s) though.
It seems like schools with rolling admissions will look applications as soon as they are complete (with GRE scores, pre-req grades, etc.) Others, will wait until their stated deadline and decide then. During your year taking A&P, find a job as an PT aide to make some money and gain a ton of hours. I would also try to find an internship in an in-patient setting, to echo what xMerryx said about the more/different experiences the better.