Yes, you can change your service area after launching Local Services Ads. You can adjust the locations where you want to offer services as your business needs change.
Keep in mind that changing your service area can affect your lead volume, competition, and overall ad performance. Expanding into new areas may increase your potential customer base, while narrowing your coverage can reduce the number of searches you are eligible for.
Before making a major change, make sure the new areas are locations you actually serve and can respond to quickly. It is also worth monitoring lead quality and cost per lead after the change to see whether the new targeting is working.