A US registration stays alive only if its maintenance filings are made in their windows. Miss one, grace included, and the USPTO cancels it — and a cancelled registration cannot be revived. The name has to be applied for again, from the start.
The declaration of use falls between the fifth and sixth year after registration; the renewal with another declaration between the ninth and tenth, and every ten years after. Each has six months of grace at a higher fee. Nothing can be filed before its window opens.