Have never seen a issue where could not get an IP on new machine connected to cable modem after reboot of modem.
If you change the mac of the device - reboot the cable modem. I personally have lots of different vms running different distros I can bring up as my router/firewall.. All I do to move to different one other than my main pfsense one is just use the same mac on the wan side connected to the cable modem via the vswitch.
I maintain my public IP this way and don't have to reboot my cable modem.
Now what I would like to see is a way to maintain my IPv6 PD so that is not changing every time you turn around ;) Then I could go native vs tunnel…