As the title of the thread says, The 2.2.11 update to SRB2 now adds the ability to raise the framerate cap.

Its more so the addition of framerate interpolation rather than changing the actual Ticks per second (TPS)

Additionally, a few stages had small layout changes in accordance of larger scale mod characters. Most noticeably, Egg Rock Zone acts 1 and 2 had its vents resized, and a gravity section altered to work on jump based activation. (This means regardless of how tall or short your character is, they will always swap gravity upon jumping.)

Are the rules going for both the main game, and modded character extensions going to change based on this? Will it be allowed, or will runners have to cap the framerate to 35 like in older updates?

It's not that "runners had to cap" the game, the only way prior to this update to have interpolation was to run on a non-official client. That's no longer the case however non-official clients are still banned. addition I didn't add it here but yes you can now run RTA with uncapped but only on the official 2.2.11 client.

As for the changes in 2.2.11, they are pretty small so will probably not make a huge deal. The biggest 2.2.11 change for the RTA speedrun is apparently now the DSZ3 boss no longer casts a shadow, and ERZ1 is faster now. We didn't create a separate category back in 2.2.8 for the last version containing the Hyperwall glitch and I don't think we'll be making one now for something a lot smaller. If some significant change happens like a full revamp or addition of a stage though then there will be a new category.

Hope that helped your question but feel free to ask here or in our discord (probably better, this site sucks for sending updates)if you have any more questions. :)