Section 20 of the Builders Lien Act provides that liens must be filed within 45 days of termination of the head contract:
Time for filing claim of lien
20 (1) If a certificate of completion has been issued with respect to a contract or subcontract, the claims of lien of
(a) the contractor or subcontractor, and
(b) any persons engaged by or under the contractor or subcontractor
may be filed no later than 45 days after the date on which the certificate of completion was issued.
(2) A claim of lien that is not governed by subsection (1) may be filed no later than 45 days after
(a) the head contract has been completed, abandoned or terminated, if the owner engaged a head contractor, or
(b) the improvement has been completed or abandoned, if paragraph (a) does not apply.
(Builders Lien Act, s. 20, emphasis added).
When termination occurs will be governed by the terms of the contract between the owner and the head contractor. In Alexander Construction Ltd. v. Al-Zaibak, 2011 BCSC 590 the court found that the provisions of the contract that required termination to be in writing were binding and that the earlier verbal notification the owner provided to the contractor was not valid to terminate the contract.