Ethereum's Pectra upgrade activation involved a critical monitoring window spanning two epochs (approximately 12.8 minutes), during which developers confirmed block proposals, voting rates, and awaited the first epoch finalization

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During every Ethereum hard fork, there is roughly a 12-minute period — the time it takes for two epochs — where over a hundred tireless Ethereum developers vigilantly monitor the state of the network for signs of problems, wondering, Did we do enough?

One epoch is roughly 6.4 minutes, the period of time it takes for a random committee of Ethereum validators to propose and vote on the validity of new blocks. It’s the time taken for up to 32 blocks to be added to the chain. The first two to three epochs are the danger zone where any issues from a new upgrade are likely to rear their ugly heads.