FS2Crew have annouced that they are doing an FS2Crew addon for the iFly 747-400 and are pairing it up with a similar software to GSX!
According to early information given by iFly it will include the voice control system of all the previous versions of the software and will also feature a button control version much like the 777.
ETA for the the iFly 747 and UGCX is still to early to say. But the 747 should come pretty quick since the iFly SDK is very comprehensive and the iFly programmer is very easy to work.
Also, Boeing has standardized a lot of their procedures between aircraft, so a lot of the 777 stuff can be ported over to the 747 because they share many common SOPs.
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