And frankly this buiness about training archers is forgetting that there were no professional armies back when the longbow was used. Villages were required to have their men practice but that was spotty.
There is no reason a fit man cannot learn to use a longbow well in a few months of hard training. You just need a good system and training regimen.
Sorry but yes there is. As perhaps one of the few people on this board who owns an accurate reproduction of a longbow and has trained to use it, believe me, to use it to anything like its full potential requires more than a few months training. The need to build up the muscle strength takes quite some time and is best done when still young (one of the reasons I only have a range about half of what was normal for the time). Also bear in kind that a longbow, except in the hands of an expert shot, is not a precission weapon. you fire it in large numbers at a large body of advancing men and hope that sheer numbers mean they will hit home. Not so far different to muskets of the tiem to be honest.
The expert shots were the longbow version of the baker rifle-armed soldier, a few of them might be of use.