The Dev's are using time dilation as they develop P4.
In the theory of relativity, time dilation is an actual difference of elapsed time between two events as measured by observers either moving relative to each other or differently situated from gravitational masses.
So where our two weeks is passing at the speed of real time thier two weeks is passing at a much slower speed thereby allowing them to accomplish much more in the same timeline. What the actual differential is only the Dev's know and all we can do is assume that at some point they will make their way back onto our plane of existence where their existence will coincide with ours and P4 will be released.
No, I don't understand it either but it sure sounds good!