Laxative former queen's brought from the East (5)

I haven't cracked this one yet — but the brilliant team at Times for the Times have:

ANNE’S (former queen’s) reversed [brought from the East]. I note that after years  of being clued as ‘queen’,  Anne has become a former queen, presumably to go with ER who is now referred to as ‘former’ more often than not. I’ve never seen the point of this as the title and cipher of a Monarch live on after their demise, and more generally historical references do not need to be qualified as such.