That's one of the last lines that Bloody Mary says at ep.3. I wonder if she is talking about the Queen of Hearts?
lol. I posted a discussion on this a few days ago. We seem to think so. Right Here
To me, it's obvious she was refering to Snow. Contextually, she was talking about the CM's relationship with the new government. She says "out with the old and in with the new", which clearly relates to Crane being deposed and Snow taking his place as Deputy Mayor.
"Long Live the Queen " in this context is a shortening of the old phrase, "The King/Queen is dead, long live the King/Queen", which would be stated upon the succession of a new monarch.
All this talk about the Queen of Hearts or the Evil Queen is just missing the point.
"Out with the old and in with the new" - time to change things. Queen Mary I of England was known as Bloody Mary.
The origin of "Bloody Mary" is the result of the demonization propaganda against Queen Mary I of England by the protestant victors.
The prods made her a spooky character to scare all generations to come and they did their job well, since the legend spread to all english colonies where it still exists today.
So I think she refers to herself.
[In passing, if catholicism had prevailed in England, there would be not Bloody Mary but "Good Queen Mary", on the contrary Elizabeth I would be "Bloody Bess" rather than "Good Queen Bess". History is written by the victors...]