Thanks Karnak, just what I was looking for.
Hope the P38 is on the list for the future.
Not for a long time. The only American aircraft not yet updated are the A-20G, B-26B, F4F-4, FM2, SBD-5 and TBM-3. Those and all of the other nineteen aircraft yet to be updated will almost certainly be updated before HTC touches any of the aircraft that have already been updated.
The remaining 19:
A-20G
Ar234B
B-26B
B5N2
Bf110C-4b
Bf110G-2
Boston Mk III
D3A1
F4F-4
FM2
Ju88A-4
Ki-61-I-Tei
Ki-67
Me163B
SBD-5
TBM-3
Tempest Mk V
Yak-9T
Yak-9U
Edit:
If I were the one choosing the next to be upgraded it would be based on usage or to make the reward units better looking or on age.
Oldest:
B-26B
Ju88A-4
Usage:
Bf110s
B-26B
Reward:
Ar234B
Me163B
Tempest Mk V