It's time for another Conzil prediction.
I think that 
Horde F2Ps will be able to queue for Island Expedition but 
Alliance F2Ps will not.
You see, on the PTR, the way you queue is by talking to the NPC next to the Expedition Map table (
Captain Rez'okun for 
Horde, 
Flynn Fairwind for 
Alliance). Right now on live servers 
Flynn Fairwind is phased until you do the quest 
Island Expedition, but 
Captain Rez'okun is not.
On live you currently queue by talking to the Expedition Map Table and I think Blizzard will do another whoopsie when they change how to queue which will allow 
Horde to queue.