A battery is just that an accumulator to store engergy, it does not matter what the label says, ford or non ford, incidentally ford DON'T make batteries, they supply them made by others, but with a different label.
A vehicle does not have any way of knowing what label is on the battery, most likely in the case above FORD found the fault when they by chance were doing some work and fitting a new battery, but if this were the case then why would all DIFFERENT battery people be in business ?
You have one of two things happening, either a constant drain, or a dodgy alternator with leaky diodes.
Try disconnecting the alternator to see if it is ok then if nt ry the drain idea.
tabetha