We have an 18 Titanium auto and the first service was done on it's first anniversary by a Ford main dealer at approx 5000 miles. As your vehicle is under warranty for I presume the same as ours ie 3 yrs, one has to be very careful about servicing. I am not sure if it was a general case but I know Honda tried to wriggle out of a warranty claim as the car had been serviced by an independent garage. The case was found against Honda, as I say I do not know if this was ruling to affect ALL makers.
The benefit of it being serviced by a main dealer sometimes brings extra benefits ie Breakdown insurance etc also there is the so called perforation warranty check done every year which the dealer either keeps a record of or stamps the book. More usual is record is kept. Should you be very unfortunate and have a rust problem and it was serviced by a Ford dealer they can't wriggle. I believe that some Focus models were badly affected by rust on the rear door.
I am perhaps fortunate in that now I do not pay for servicing as it is a Mobility car. Our previous car (not a Ford) was serviced by a dealer as part of a deal but as soon as that ran out I went to an independent. It actually worked out more expensive BUT I did not have to travel so ar and I was allowed to watch ( most large garages will not allow this) and discuss any problems with the mechanic. Speak to the people that sold you the car voicing your concerns and if you have a small independent that you know speak to them BUT only you can decide.