I will be applying for the 2015 cycle this summer and plan to apply right away in July. I have 140 observation hours under my belt in two different settings and have met many wonderful PTs along the way. There are two PTs I am considering asking for LOR; however, because I plan to apply in four months and am thinking about reaching out to a different setting how should I go about asking them to write me a good LOR in the future? Should I ask now? Reach out to them later? What is the proper way to do so?