The Ethereum Foundation chose to create the Hoodi testnet specifically to test validator exits, avoiding complications that would arise from clearing Holesky's exit queue

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According to the call on Thursday, the developers agreed to launch a new testnet rather than pursue other proposals. Hoodi is set to specifically give researchers a dedicated network to test validator exits, which would not be possible on Holesky due to a backed-up exit queue. Holesky and Sepolia will operate to test other research concerns.