Take a look at https://github.com/code-423n4/2024-03-zksync/blob/4f0ba34f34a864c354c7e8c47643ed8f4a250e13/code/contracts/ethereum/contracts/common/Config.sol#L35-L39
Evidently, the PRIORITY_EXPIRATION is set to zero, but this is meant for the Alpha release period which ended in April, now consider https://github.com/code-423n4/2024-03-zksync/blob/4f0ba34f34a864c354c7e8c47643ed8f4a250e13/code/contracts/ethereum/contracts/state-transition/chain-deps/facets/Mailbox.sol#L258-L287
We can see that the deadline parameter uses this value PRIORITY_EXPIRATION to determine the deadline for the validators to process this transaction, but the value being 0 would mean that all transaction would use the timestamp the transaction was requested, which would be logically flawed.
Outdated code still in production.
Since the Alpha release period has passed, the necessary value for PRIORITY_EXPIRATIONshould be passed and stored in Config.sol
