Hey buddy
I suppose we'll learn a bit more about all this soon, but i just downloaded vplanner to have a look at rough run times on 21% O2 35% He.
www.hhssoftware.com/v-planner/download.html
Not sure i used it properly as it's the first time i've had a play but, a 45m dive with a 30 min bottom time, gave this... (I know it's not DIR as we'll be doing deco on the fly, but it gives a rough example).
Dec to 45m (3) Triox 21/35 15m/min descent.
Level 45m 27:00 (30) Triox 21/35 1.15 ppO2, 21m ead, 26m end
Asc to 24m (32) Triox 21/35 -9m/min ascent.
Stop at 24m 0:40 (33) Triox 21/35 0.71 ppO2, 9m ead, 12m end
Stop at 21m 1:00 (34) Nitrox 50 1.54 ppO2, 10m ead
Stop at 18m 1:00 (35) Nitrox 50 1.39 ppO2, 8m ead
Stop at 15m 1:00 (36) Nitrox 50 1.24 ppO2, 6m ead
Stop at 12m 3:00 (39) Nitrox 50 1.10 ppO2, 4m ead
Stop at 9m 3:00 (42) Nitrox 50 0.95 ppO2, 2m ead
Stop at 6m 6:00 (48) Nitrox 50 0.80 ppO2, 0m ead
Stop at 3m 10:00 (58) Nitrox 50 0.65 ppO2, 0m ead
Surface (58) Nitrox 50 -9m/min ascent.
Bri