If you have to leave the country Phnom Penh might be a better option. Some outfit is already advertising "visa runs" via air, including all re-entry costs.
Jeh Rhm. Under the current policy you will be eligible for one more covid extension around the middle of March, which will take you through to the middle of May. I'd say it's highly unlikely there will be more covid extensions, as travel is now very easy around the world