Strange odds for tonight.

There must be some strange things going om prior to tonights match at Old Trafford.
Whilst it seems common knowledge that they will make changes as they regards the Liverpool match as more important, the betting odds have changed dramatically over last few hours.
Yesterday a City win was 5/2, this morning it was 7/4,lunchtime both clubs were roughly the same at 6/4 to win, now we are heavy favourites to win , and United are about 9/4.
This is such a big swing towards us that the bookies must know something.
Are United going to field a youth team, are they resting many players.?
Hopefully this will work in our favour, and we will get the result we desperately need.
It seems that results and circumstances are going our way, lets hope we take advantage and go into the Cup Final on a good win.
Would be so disappointing if we miss out on Champions league now.