As much as I would like to say its not, this is my first regex rodeo. Can you give me an example of it in use (ideally in my use case 
) to help cement my understanding.
If they push 1 or 0 it forces an early match, otherwise it has to be a 10-digit number starting between 2 and 9.
Would it be like this?
^({0!}|{1!}|[2-9]{1}[0-9]{9})$
Thanks again for the guidance!