I've asked this multiple times on the server itself, and I've gotten a different answer each time. As such, I'm asking the staff straight up, will the server, specifically the TARDIS dimension, be reset with U47?

We don't know yet. When U47 is closer to completion it will be tested for compatibility with the map. If it's not compatible a reset'll be necessary,  if it is compatible  there won't be.

Thank you for the quick answer. I appreciate it.