I was supposed to have my CFI-I checkride down in Florida this past weekend, but unfortunately Hurricane Irma messed that up. When I received training for this checkride, I completed it along with my CFI-A training, and therefore was endorsed at the same time. I'm coming up on 60 days since completing 3 hours with the instructor that signed me off for the checkride. However, after reviewing the endorsement, nowhere does it say the three hours has to be with the same instructor. Basically my question is if I were able to log an hour or so of training with another instructor, would that extend the valid time of the endorsement?