If players want to use the new cards and items featured in the Daybreak expansion I presume the mutiny deck must be used as the colonial 1 overlay and alternate treachery cards use them. However, are they able to use the sympathiser or sympathetic cylon variant rather than the mutineer option? And if so, is the mutiny deck still used?

Ok, the following items comprise the core of the daybreak expansion and must be used all together or none at all

->daybreak skill cards, daybreak crisis, assault raptors, mutiny deck, colonial1 overlay, characters referring to mutiny or miracle tokens on their sheet.

If you want to use the mutineer balance mechanism for 4 or 6/7 players you mist be using the daybreak stuff above

Separately you can choose to use or not use the cylon leader or symphiser mechanics to balance a 4 or 6/7 player game.

Why anyone would ever use the sympathiser or sympathetic cylon when they have access to the cylon leader motives or mutineer that comes with daybreak is baffling as the old mechanics were horrible and broken

Sometimes I shuffle the mutineer into the start of game loyalty cards to rig the deck deliberately otherwise it can be no penalty at all.

Okay cheers. So (if you did want to) you can swap out the mutineer card for the sympathiser or sympathetic cylon? And any of those three cards is supposed to be added only during the sleeper phase? Or does the mutineer card actually go in from the start (never been clear on that).

Mutineer goes in from the start, in fact it's rather unbalanced if it doesn't come out first half (sometimes we house rule rig this so it happens)

Sympathiser is definitely only mixed in at sleeper.

I don't usually use the sympathetic cylon so would need to look it up.