I've contacted the IPO staff as early as 6 months out. It kind of depends on what you'd like them to do for you. Most PS's can't be made until 90 days out, but they'll still take your requests and update them as the time gets closer. If you're interested in Cirque tickets, Hoop De Doo, the chefs table at Victoria & Alberts, or maybe making arrangements to celebrate a special event, these are things that can be taken care of sooner. I'd definitely recommend that you drop them an e-mail, give them your address and request that they mail out any pre-planning packets to you. At the Epcot resorts, you'll deal with Alana, Amy, Angie & Lauren. They are probably the best of the best. Their packets include park maps, recreation gudes, a questionnaire and resort information. You can talk to them about any allergies, or food issues, room requests, special arrangements, shopping for gifts to place in your room, basically whatever you need.
Here is the e-mail address for the Epcot staff,
WDW.YBBW.Concierge@disney.com. You are in excellent hands.
OOPS, sorry I just noticed that you've already stayed at the BC concierge and you're looking for the Poly info. Here you go,
wdw.polynesian.island.planning.office@disney.com
Tammi