For 'rumrunner':

I think it depends on whether your visa is a 'multiple entry' or was a 'single entry' one.

If it is multi-entry, then you should get three months stay granted by the passport examiner at the airport on your return.

If you want to stay longer than three months, then (after two months) apply for extension to stay and that three months will be changed to one year from the date of arrival. That extension can be renewed (further extended) one year at a time. But you must then get a re-entry permit, before you leave, each time.

If it was single entry, then you need to get a new one before coming back (unless you are coming back for less than 30 days.)

As said we need to know what you really have. Did you submit police report/medical at a home country Consulate to obtain this visa? If not it is likely a non immigrant O visa (to check on retirement) rather than OA.

If it is a single entry OA and you departed without a re-entry permit after having used it, it is no longer valid.

If it is a multi entry OA visa any entry will receive a one year permitted to stay stamp for the validity of the visa. After the validity of the visa you will require a re-entry permit for any travel to keep the current permitted to stay time alive.