You can culture the seedlings without dormancy through the winter, if you use sufficient lighting. The dormany is primarily important for the health and the flowering ability of a adult plant. Seedlings will thank you skiping it with faster growth. Water them regulary but let the substrate dry out in between to prevent rot.

If you intend to send them into a winter dormancy, stop the water about one month prior, make sure the substrate is dried and bring them to a cold spot about 5°-10°C, max. 15°C. Do not water them! If you do, they will grow long and thin because of insufficient light. Also it unnecessarily brings the risk of rot.

The seedlings can be kept together in one pot for a long time, until they are about 15 - 20cm. Having company boosts their growth.

If you have more questions dont hesitate asking