XBleed,
The FOs Hold Pool is managed by HR, who get advice from the workforce planners. HR are still doing roadshows, interviews and testing, so the hold pool is constantly being reviewed.
Workforce planning are aware of the imbalance between the Airbus/Boeing/A380 rates of effort, and re-distributing internally off the shrinking fleet, is just one method that might be used to address the Boeing/A380 shortfall and the factoring issue.
From a company perspective, delaying you until Sep/Oct would make sense if there was a priority for internal training, or the aircraft which you were being allocated were not delivering until early next year.
I don't know much, however when you do get a call to join, I can almost guarantee that you will be flying out of Dubai, on international routes, in a wide-body, with Emirates livery. Good luck.