The report claims that production for both phones are expected to kick off in July. This follows a recent rumor suggesting that both Foxconn and Pegatron, Apple’s assemblers for all things iOS, have begun a hiring spree that would get both companies up to speed and capacity for production. Bloomberg claims that production in July means that both devices will be on track for a simultaneous launch and release.
However they do note that production of the 5.5-inch model is allegedly more complicated than that of the 4.7-inch model, which basically seems to suggest that availability of the 5.5-inch model could be constrained at the start. Bloomberg did not mention anything about the possibility that the 5.5-inch model could cost $100 more.
In any case take it with a grain of salt for now, but for those who are eyeing the 5.5-inch model, looks like you could be in luck, assuming you move fast enough to grab yourself one before they are sold out!