When you get to Epcot you go to the kiosk and make the fp reservation. If you are staying CL you can text the concierge or if you are going back to the hotel in between you can ask the concierge there too (in person not calling or texting )
I don't even think that would help improve availability at Epcot. when I was there the only attractions available in the pm were: Figment, EO, LWTL and MS (for 9pm).