I'll be in London for the month of May 2015. So far as I can determine the only sold-out shows in London at that time are Man and Superman and Closer to Heaven. I know the ways to get into sold-out performances(day seats, trying for returns, etc.). My questions are, however, (1) What other shows(if any) might prove to be tough tickets to get and should be purchased in advance of May? and (2) Is Imelda Staunton likely to do all evening and matinee performances of Gypsy? Thanks for any help you can give me.