A supplier first delivered materials on Day 1 but served its preliminary notice on Day 40. For which materials may it claim?

解析

Civil Code §8204(a) provides that a claimant who did not give preliminary notice is not precluded from giving one later, but is then entitled to claim only for work performed within the 20 days prior to service of the notice, and at any time thereafter. Service on Day 40 therefore protects deliveries from roughly Day 20 forward, and the deliveries from Day 1 to Day 19 fall outside the window. (b) treats a late notice as fatal, which the subdivision expressly says it is not. (c) ignores the look-back altogether. (a) counts 20 days forward from service instead of backward, which protects nothing the statute protects.