So is there a way to extend this thing?

So I know I remember seeing bout you know legacy gametypes and maps from the old 360 halos transfer over to the one so I read the date thinking that was the date it would be starting on till I re read it a couple days ago finding out that was the date to have it in by. Is there any chance of it being a little bit extended for gametypes? Also how do I transfer the gametype/maps from 360 version to one fileshare?

If you haven’t uploaded the game types already then I believe it’s too late, I’m afraid; the copy of those has already happened, so you’ll have to wait for if and when they do this again (and that’s a very big if).

Maps can still be uploaded before the 26th—all you have to do is load up the legacy versions of each game (on the 360 or via backwards compatibility), move whichever local maps you want to transfer into your file share, and leave them there. They will be copied on the 26th, and become available whenever MCC Reach releases (that’s the current plan, anyway).

For more details see here, under the ‘LEGACY CONTENT MIGRATION’ subheading.

Sadly, it is too late. The next transfer is for maps which will be August 26th so be sure you have that in order before hand.