Events potentially affected in the 6 to 8 Week period:
Leeds:
Sabaton - The Tour To End All Tours - 14th April
Michael Starring Ben - 22nd April
Magic Mike Live - 29th April
Andre Rieu - 11th May
Sheffield:
Magic Mike Live - 26th April
Andre Rieu - 13th May
Glasgow:
Sabaton - The Tour To End All Tours 18th April
Magic Mike Live - 25th April
Manchester:
Rob Beckett & Josh Widdicombe's Parenting Hell Live - 14th April
Magic Mike Live - 2nd May
Birmingham:
Elton John - 19th April (nearly sold out)
Newcastle:
Nothing booked
Liverpool:
Nothing booked
Leeds simply looks to have too much on during that period. So that is going to be a big issue for the city to get past. I just can't see it happening.
I REALLY can't see Elton John getting the boot, unless Elton is personally up for that (unconvinced) - but the costs of postponing are going to be pretty high. I am not sure thats going to be viable. So that would kill off Birmingham's chances unless Elton is happy - the fact its already nearly sold out is a big issue.
Sheffield, Glasgow and Manchester ALL have two things on, which complecates things: Not sure what to make of the Magic Mike problem. I suspect cancellation or changing the date is possible but expensive. It probably depends on ticket sales so far.
Having said that I suspect the staging for Rob Beckett and Josh Widdicombe's thing could work around Eurovision or they wouldn't mind postponing which might give Manchester a slight advantage here over Sheffield and Glasgow.
That means Liverpool and Newcastle appear to have at least one thing significant going for them because the venues aren't busy in April/May next year.
On venue issues alone, you'd have to put in this order of viability:
Liverpool / Newcastle
Manchester
Sheffield / Glasgow
Leeds / Birmingham
Which given that Glasgow and Birmingham are the bookies fav is slightly interesting.