So my friend has a couple of ~70cm pedros and is wondering when it's the best time of the year to cut, let it pup, and root the cuttings. Just before spring? In the middle of winter, so that they have time to callus before spring?

Now it's winter, with minimum temperatures of 2-3°C. Freezing temperatures are very rare.

for the health of the plant, spring is warmer and drier typically, but i've had good luck harvesting as things froze back and some tips died during winter