Board Thread:Wiki-Related Discussion/@comment-25315804-20170518042500/@comment-1916997-20170523155619

The wiki does it like this:

B1: Everything that happened before Regina cast the curse that we see in the Pilot.

D1: Everything that happens in the time from when SB is created (as seen in Welcome to Storybrooke) to when Emma gives Henry TLK and restores everyone's memories.

A1: Everything after the TLK until Regina undoes the curse at the end of 3A.

B2: Everything from when everyone (except Henry and Emma) arrive back in EF, until Snow casts the curse.

D2: Everything that happens from when SB is recreated til Regina gives Henry TLK and restores everyone's memories.

A2: Everything after the TLK until Issac makes the AR.

AR: Everything that happened while the AR existed.

B3: Everything that happened after the AR is destroyed, until Hook casts the curse.

D3: Nothing, as the curse was just used the get back to SB.

A3: Everything that happened after Emma & co. got back from Camelot, until the Black Fairy's curse.

B4: Same as A3.

D4: Everything that happened after the curse was cast, until it is broken by Henry giving Emma TLK.

A4: Everything that happened after the TLK, until a new curse is cast (which seems likely given the things we have heard about Season 7, but we will have to wait to find out).