Which ports will be my instance be using, after migration?

I have an installation that does not use default HTTPS and SIP ports, will they remain the same after moving to hosted?

All SIP and Tunnel ports will be reset to the default values (5060 for sip and 5090 for tunnel services). The default web port will be set to 443,  or you can opt for 5001 when restoring a backup. 

In case you are using a different HTTPS port, you must choose between 443 (default) or 5001. Restart end-points, such as 3CX APPs and IP Phones to update the new SIP and Tunnel ports after the migration. If the HTTP port is changed you need to reprovision the devices again.