That seemed to be the case, Vinny. I guess the explanation could be that all of the internal MCC team was repurposed to focus on Halo 5.
Still: experienced internal developers > external developers.
(Which is reason to have some faith in this new effort by 343i imho.)
Also, they seem to be starting in the right end: fix the things that entail refactoring large parts of the code base. Fixes that are simply very difficult to develop, test, and release in an "live" environment. Then, when the core parts of the code are refactored and fairly stable, it would make sense to start working in more isolated and "minor" issues, such as the game-specific issue (think the http://halobugs.com buglist). Hopefully that is also the 343 Legacy Team's plan.