Depends on how far you are moving - Doctors usually have a limit as to how far they are willing to travel in case you need a home visit, and that is what sets their catchment area. They may be willing to keep you on their register on the understanding that they will not supply home visits, as these are a very rare occurance these days, you may find that the doctor is happy to keep you on that basis.
However, if you were then in the sudden need of a home visit, you may find it difficult to then register with a new doctor that quickly.