This post https://www.reddit.com/r/antiwork/comments/wi4xnq/called_in_on_my_day_off/ is the reason for this post. I do this when I'm looking for a new job: get a new SIM card (prepaid) and use this number during the process of getting a new job. And when they hire you then you can just discard this SIM card (these days mobile phone are dual SIM so no problem there. BUT: you must be sure you call them from the *temporary* phone number and not your private phone number. So they can't reach you. If you get a phone at work: switch it on when you get to work and switch it off when you leave (unless of course you get some additional money for being available 24/7).