Ok, an update on my engine budgie..
He's gone!
Picked the car up yesterday after having the waterpump, cambelt, tensioner and idler pulley replaced and glad to report no more squeak squeak squeak on startup
Also glad to report that the dealer came round to my way of thinking and got all the parts/labour past the warranty mob so it was all FOC, had a nose at my old waterpump and the spindle was actually quite tough to turn by hand hence their diagnosis of the pump bearings being noisy until they had warmed up, seems feasible enough and i'm glad it was changed either way as it definately didnt feel right!
Still inclined to think the fault lay with the idler pulley but happy to have had the lot changed and no more squeak...
Happy now!