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+## Gray Glacier Network Upgrade Specification
+
+### Included EIPs
+Specifies changes included in the Network Upgrade.
+
+- [x] [EIP-5133: Delaying Difficulty Bomb to Mid September 2022](https://eips.ethereum.org/EIPS/eip-5133)
+
+### Upgrade Schedule
+
+| Network | Block      | Expected Date | Fork Hash    |
+| --------|------------|---------------|--------------|
+| Mainnet | 15050000 | June 29, 2022 | `0xf0afd0e3` |
+
+### Client Releases
+
+ - [ ]  Mainnet
+   - [ ]  Geth
+   - [ ]  Besu
+   - [ ]  Nethermind
+   - [ ]  Erigon
+   - [ ]  EthereumJS
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