No, you would be able to activate the panel using cellular only for now, but you wouldn’t be able to update firmware, depending on the model of the replacement panel.
You can swap the panel associated with your account at any time in the system manager linked here. This would require manual programming of all zones in the new panel.
Backup restore options exist if you are switching to another Qolsys panel with the same radio type, but your panel firmware is currently too old to do that. Instructions regarding backup restore options are linked below. This is not necessary though and you could instead just use the system manager and program sensors individually.