Time is always allowed to obtain any parking ticket, including a virtual visitor permit, so you should submit representations that your wife was inside the house obtaining a visitor permit. Make sure to include a printout of the permit.
Don't expect them to cancel straightaway. You are submitting an informal challenge, and councils ruthlessly game the system by refusing virtually all informal reps, knowing that if they do, most people then just cough up, not wanting to risk the full penalty at adjudication.