Here's some suggestions:
1) Don't buy any Airfix this year
2) Hope that next year things will be better for you
3) Address the stash (if you have one)
4) Buy kits in scales and genres from the myriad other manufacturers that are in the plastic kit business, that suit your taste
They couldn't do anything for D-day in 1/48 either; how hard would it be be to knock together a D-day set similar to the battle of Britain one
I'm struggling to think of which kits, other than the P-51D, that are available from the current tooling catalogue, from which you could 'knock together' a D-Day set. Give us a clue.