I’m going to stick with the 90s interval for this week and see how things go, probably moving back to the 85s interval next week.
Today my 50m reps were almost all 44s, with one 45 and one 43. I was really quite tired afterwards though, and struggled to get into the 18s with my 25m reps. I suspect I started a little late and didn’t get as much rest time as normal between the two sets. Hopefully it will be better tomorrow.