Did anyone call the office, and ask if "end of summer" could be taken literally as per our calendar?

Well, yes I did call the office to get a definition of end of summer and was told that it was thought to mean the end of the summer solstice, or September 21st rather than the end of the summer holidays, for example. I believe that others also called and received the same information. In my case I was told the date came from Tetra Tech, not a Copper Fox management deadline.