RelayHub contract doesn’t receive payments, the payment for the service (in tokens) is sent directly to the worker relaying the transaction on behalf of the user.
RelayHub contract now handles relay manager staking.
Gas estimation improvements:
GasOverhead removed from RelayHub, there are no more validations against hardcoded values
Now the gas and tokenGas fields from the request can be left undefined, and in that case they will be automatically estimated by the RelayClient.
The maximum gas estimation in the RelayServer is more precise now
A new utility function is available to estimate the maximum gas a relay transaction would consume, based in a linear fit estimation. This can be used in applications that don’t want to sign a payload each time they need an approximation of the cost of relaying the transaction
Paymaster verifications are done off-chain to optimize gas costs, thus the paymasters are now called Verifiers and they are not part of the on-chain relay flow nor they handle payments at all.