You should be fine extending veg until the end of December. Your plants still have plenty of vertical space, and as long as you keep training a flat canopy you can easily control the height. Topping anything that rises above canopy level is a good plan.
Just keep the branches spread wide and fill the tent horizontally before flipping. The structure looks healthy and compact, so you’re in a good position for a long veg.
If you feel they’re getting too bushy, you can remove some lower growth or light defoliation to help airflow.
At 23°C and ~65% RH in organic soil, they look happy. Keep training and you won’t run out of space