[2023] Hello, silly question. MCC and Infinite

So I have MCC on Xbox 360, have had it a while now. It has been several months since I've logged on to play but I could've sworn infinite maps/game was part of it. I even googled Infinite maps and know for a fact I played these maps in multi-player social game mode several times. I'm really only comfortable with Halo CE and Infinite and no one ever goes on the CE games anymore it seems. They played more on Infinite which increased the games I was able to play. Anyway, was just wondering if the Infinite maps being part of MCC was limited time only or am I really just not remembering something correctly?