Constant forest_actor::miner::FAULT_DECLARATION_CUTOFF

pub const FAULT_DECLARATION_CUTOFF: ChainEpoch = WPOST_CHALLENGE_LOOKBACK + 50; // 70i64

Minimum period before a deadline’s challenge window opens that a fault must be declared for that deadline. This lookback must not be less than WPoStChallengeLookback lest a malicious miner be able to selectively declare faults after learning the challenge value.