Today the guys over at iFly have announced that they plan on releasing an update to the 737NG series to make a HD texture pack for the 64 bit P3Dv4 as well as an update for the 747-8i for P3Dv3 and v4 sometime in 2018. iFly has stated that the update for the 747 will be a free update to prior 747 customers.
iFly also announced their next project the 737MAX. The 737MAX will only be released for P3D 64 bit. Now bear in mind they announced a projected release date of the first half of 2020. As I said this is a projection and is by no means a set date. The 737Max series in the real world is still in development to put things into context