Height 5' 9" ( used to be 5' 11" but I seem to have shrunk) about 1.75m
Wing span about the same.
Green zone for SPL (25m) should be about 18 but is usually over 20 and sometimes 25 or higher.
I have established that tempos between 0:50 and 0:60 for Mode 3 seem to be manageable. Each length takes up to thirty beeps and sometimes maybe 33 with about five or six for push off and maybe three for final drive for the wall, depending on where the last stroke is made. Will experiment with final fast stroke, which might reduce number of beeps.
Times in seconds have been between 33 and 38 , with some uncertainty about timing of start and finish on Timex Ironman watch. There would be less variation, I'm sure, with 50m, 75m and 100m repeats but so far I have done only 25m repeats. I'm pleased with the consistency that the TT seems to provide.
Finding the right starting range for backstroke may take some time.