I feel like it is time to de-flask now coz your babies are actively growing & I saw some yellowing leaves at bottom parts.
I'm afraid if keep them in flask for too long, the bottom part may start to rot eventually.
If you decide to de-flask, I recommend sphagnum moss(with some Styrofoam peanuts as drainage in bottoms) as growing medium for young seedlings since it can provide high humidity to seedlings.
You can either plant them individually in thumb pot or in community pot. Wash carefully & soak with some fungicide solution to keep them away from fungus & rot problems.
The most important aspect is humidity. As you can see in flask, seedlings are grown up in almost 100% humidity environment. If sudden environment changes such as too dry place & direct sunlight will cause them stress. Keeping them together will also increase humidity.
Phal violacea is warm loving species, so providing warm & high humidity place with some bright , indirect sunlight will accelerate their growth. Don't use fertilizer until you see some progress on new leaves & roots development.
Oh I'm so long winded. I must stop here