I believe we're following the Man City Academy style that everyone will play one age group above them. So our U14s are playing against U15s. Our U16s against U17s, etc.
This is definitely not the case. This only happened for the NYCFC teams this year because of the half-assed nature of the Academy. Rare to find more than a few players on any team that are playing up in the Development Academy and there will be fewer going forward now that they've created a standalone U15 division.
If we played all teams up a year we'd get our asses handed to us on a regular basis.