14 CFR § 141.17

Unless surrendered, suspended, or revoked, a pilot school's certificate or a provisional pilot school's certificate expires:

On the last day of the 24th calendar month from the month the certificate was issued;

Except as provided in paragraph (b) of this section, on the date that any change in ownership of the school occurs;

On the date of any change in the facilities upon which the school's certificate is based occurs; or

Upon notice by the Administrator that the school has failed for more than 60 days to maintain the facilities, aircraft, or personnel required for any one of the school's approved training courses.

A change in the ownership of a pilot school or provisional pilot school does not terminate that school's certificate if, within 30 days after the date that any change in ownership of the school occurs:

Application is made for an appropriate amendment to the certificate; and

No change in the facilities, personnel, or approved training courses is involved.

An examining authority issued to the holder of a pilot school certificate expires on the date that the pilot school certificate expires, or is surrendered, suspended, or revoked.