I don't want to go into too much detail here other than to say, our access to the development Fiesta should be unhindered. Consider the R&D process still in a joint capacity with Adam. He is actually currently running our prototype intercooler to develop tunes for it, for example. To specifically address your concerns, I don't foresee any scenario in which R&D would be held up for any reason as we are both still working together towards the common goal of increasing the fun factor for this platform!
On another point, believe me...if we DO bump into a hurdle, for any reason, that causes an ongoing situation where our access is limited (again... something I really don't think is very viable), we would probably just spring for another car.
I hope that helps put your concerns at bay