You should be able to transplant it now if it is starting to develop roots in the water. Start getting in a habit to test the potting soil and water it when it feels almost dry or dry. You can also put it outside where it gets morning sun only during the summer months. Cold winter temps should not be a big issue this year but if they become cold, I would bring it inside for a few days and then return it outside. Up here, we have had temps dip below 32 5-6 times only and even fewer times below 30. Just do not keep it inside for months on end as they prefer the outside weather.

Here is an article on growing camellias in containers by the American Camellia Society:

https://www.americancamellias.com/care-culture-resources/general-culture-requirements/container-grown-camellias

I never knew you can root a camellia in water!!! I must give it a try now.

i would cover the cutting in a vented plastic dome to increase humidity after planting while its roots transition from water to soil. give it bright light but keep it out of direct sun while tented until active top growth is seen and slowly acclimate it to normal container (or garden soil) culture.

elena, your description of the flower sounds like it could be 'debutante'.

click for camellia 'debutante'

Now that is a very cute bunch of roots.

I would be inclined to pot it soon, because the sooner you pot it, the less likely you are to damage the roots.

You would be best to choose a very good quality potting mix that is for acid-loving plants. And a nice, clean pot, not too big or you run the risk of over-watering your plant. Perhaps a 4" pot.

Always water well immediately after potting. It is the most important watering that you'll ever do. And saturate the soil mix. After that, water only when you 'have the feeling' that your should. And I would also spray it overhead with a mist spray because I like to fuss.

Never leave water sitting in the saucer. (The only time to leave water in the saucer is when trying to re-wet potting mix that has become too dry. But in that instance, it is better to use a bucket. And the other exception to having water in a saucer is if you are watering from underneath, which you won't be doing.)

I don't go along with the theory of checking the top whatever of the mix to test when to water. I like to lift the pot and judge how much water it is holding.

I agree that the description of the flower makes it sound like Camellia japonica 'Debutante'.

Good luck.