A medium sized base with two wells needs ~2-4 days moving of the wells to a new field (that was in a patch situation when the fields where better emptied than it seems today).
Considering the time effort to connect wells around the island, worth of wells and (de-)construction charges, you are by far better off mining alpha ores and haul every few days commodities for your reactor. That is in my opinion something that should be fixed in a way, that at least one medium size gamma base/island can be operated without reactor. Today I see no reason in moving wells.