If a member suffers “an injury” following termination of active service, and within the time prescribed in Section 3212, 3212.2, 3212.3, 3212.4, 3212.5, 3212.6, 3212.7, or 3213, then, irrespective of his remuneration from any postactive service employment, his average weekly earnings for the purposes of determining temporary disability indemnity, permanent total disability indemnity, and permanent partial disability indemnity, shall be taken at the maximum fixed for each such disability, respectively, in Section 4453.