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Client systems should use the A and B Incremental Feeds to arbitrate as follows:
Listen to packets from both Incremental Feed A and Incremental Feed B.
Process packets by incremental sequence number.
Discard a packet if the sequence number has already been processed.
If a sequence number gap is detected, this indicates a packet was lost on both the Incremental Feed A and Incremental Feed B. In this scenario client systems must initiate the recovery procedure.