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The only change (EIP) is:
EIP-4345: Difficulty Bomb Delay to June 2022
The EIP proposes to push the bomb back for a total of 10,700,000 blocks, an increase of 1,000,000 blocks since the last pushback, in London. The bomb will likely show up in June 2022.
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Status page: https://github.com/ethereum/execution-specs/blob/master/network-upgrades/mainnet-upgrades/arrow-glacier.md
Impact Analysis
MidChains will pause deposits of Ethereum during the node upgrade and a downtime of 30 minutes can be expected, all deposits made during the upgrade will still be processed but will have a delay until upgrade is complete. MidChains will carry out node upgrades on Sunday, December 5th during the maintenance window where trading operations are closedhas already upgraded the Ethereum nodes to support the Arrow Glacier fork. All deposits made during the forking at block 13,773,000 are expected to be processed without any impact and proceed on the authentic Ethereum chain.
Vendors
Curv confirmed their nodes where upgraded already.
Chainalysis KYT is not dependent on nodes, the addressing mechanism is not changing so there is no impact.
Clients will not experience any impact on their funds post chain upgrade.
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