Moving and need service at two addresses

We tried to use the moving service, however it resulted in an error and told us to contact customer service. The chatbot refused to refer us to a human representative, and simply took us back to the moving page that results in the error. So here we are, incredibly frustrated.

We are moving to a new address and would like a month of overlap with coverage at both homes while we move. We already have a compatible second modem, so we would like to use that at the new address. We have a contract with an early termination fee with Xfinity, so we do not want to do anything (i.e. create a second account then cancel our current one) that would trigger the termination fee when we are not discontinuing Xfinity service, we are just moving and continuing service at the new address. So we need support to allow us to keep the current service on with the current equipment, and allow us to set up our equipment at the new home with service, with overlap for a month. Paying for both in the meantime is not a problem, so long as we don't hit a termination fee for the current service. We appreciate any help.