Confirmation that the series will not return until next year was announced at the end of last night's Sherlock Season 1 finale replay.

Replay the whole scene over and over until you can imagine it from beginning to end in under 2 seconds, ideally in under 1 second.

Replay causes the Coordinator to resend the last protocol message to Database-1, which lets Database-1 deduce the transaction state -- and then apply the appropriate recovery rule.