[36] "But should it not be complete" means: when being made up, it does not suffice.
"That robe-cloth should be laid aside by the bhikkhu for a month at the most" means: it should be laid aside for a month at the longest.
"For the completion of what is lacking" means: for the purpose of making complete what is deficient.
"When there is an expectation" means: there is an expectation (of obtaining cloth) — whether from the Saṅgha, or from a group (gaṇa), or from relatives, or from friends, or from rag-cloth (paṃsukūla), or by means of one's own wealth.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.