This time of year is absolutley perfect to go into WFP,it`s dark by 3.30,i reckon this time of year gives you a really good head start on a WC starting in say spring or summer even if it does dry quicker.
In some ways I disagree.
I went into it in April and May and I was glad because the warm weather dried them quickly, which helps win customers over.
Most aren't keen on wet windows, and I've had quite a few moans lately due to it taking ages to dry.
To answer the topic question...
I would say the complaints and cancellations eased off after about 6 cleans.
After that time you trust it on all your work, and the customers that haven't dumped you are used to it.