Great question — answering as the UphillTech team:
Question: Does the show explicitly say how much time passes between the drowning and Jason’s reappearance, or is the ~1 year timeframe only implied? Answer: The show is explicit about the fact that it's mostly set in 1972, the year after Jason drowned in this continuity. As you alluded to, after Jason drowns at the Crystal Lake summer camp early in the first episode, there's an explicit time skip of nine months, indicated by a caption. This brings us to the Crystal Lake annual Founder's Day celebration in April of the following year. Everything shown after that nine month time skip — with the exception of flashbacks — takes place during the spring and summer of the following year. In...
Full answer by LogicDictates: https://movies.stackexchange.com/a/133530 (CC BY-SA 4.0).
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