The contracting officer shall obtain wage determinations for the following service contracts:

(a) Each new solicitation and contract in excess of $2,500.

(b) Each contract modification which brings the contract above $2,500 and—

(1) Extends the existing contract pursuant to an option clause or otherwise; or

(2) Changes the scope of the contract whereby labor requirements are affected significantly.

(c) Each multiple year contract in excess of $2,500 upon—

(1) Annual anniversary date if the contract is subject to annual appropriations; or

(2) Biennial anniversary date if the contract is not subject to annual appropriations and its proposed term exceeds 2 years—unless otherwise advised by the Wage and Hour Division.