Brakes gone bad after a month of storage?

Ah bad times! Got a track day tomorrow morning so got the 197 out last night for a clean and once over, it's been sitting in the garage for approx. a month and a half unattended.

During the drive to the jetwash I noticed the brakes were very poor, almost zero bite and on a damp road emergency stops from 40-50 mph aren't even strong enough for abs interaction! The pedal seems to travel a long way for very little response in the brakes, once again there is zero bite.

Took it for a 40 test drive to sweep the discs and no improvement, got heat into them and no improvement. Stripped and cleaned front calipers and bled calipers with what I had spare (500ml). Nothing seems to have improved them. Upon inspection of inner disc faces there is heavy corrosion where the pads have been sitting over winter, the fault?

Tomorrow I have a trackday so I need to decide if I should take the 197 and hope the discs sweep clean on the 3 hour drive upto Cadwell Park and the brakes come back OR if I take the unprepared 172 ( road tyres ).

Setup is RC5+ pads, ktec 2 piece discs, braided lines and motul RBF 660 fluid, never harangue problems before.

Anyone got some advice or point me in the direction of the possible fault?
 
i would roughen up the pads abit and maybe take some iron x to the dics, if not then some mosture has gotten into the fluid