Hi Azimuth!The ideal time to up-pot is when the plant can drain your last full watering in a single day. That will mean the roots have filled the pot with a root ball and will make for a stronger plant later on in flower. Then, if there is another planned up-pot, you wait for the roots to drain the last full watering in this new larger pot in a day again.
Can you elaborate on that a bit?
How do you tell?
Thanks!