I don't understand the question call Xfinity set up an appointment and then install within a week or maybe even the next day I don't work for Xfinity but call Xfinity they know
Call them
It depends in how busy they are and what you need, if your house/appartment already had xfinity in the past you can set everything up yourself the same day, if not they are usually pretty quick in having a tech do it for you. Hopes this helps
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