Suppose a validator has a sync committee duty for slot X. Is he supposed to send his SyncCommitteeMessage exclusively in slot X? Or may he send during the epoch (similarly to the attestation duty)? Could you give any reference on that?
1 Answer
For every question you have on Ethereum, I suggest you look the eth2book written by Ben Eddington which is very complete.
For instance on the section Sync committee you can read:
A sync committee does its duties (and receives rewards for doing so) for only EPOCHS_PER_SYNC_COMMITTEE_PERIOD epochs until the next committee takes over.
With EPOCHS_PER_SYNC_COMMITTEE_PERIOD=256
.