I started maters from seed last year for the first time, and have forgotten what I'd done!

My mater seedlings (Super Sweet 100 hybrid/ cherry tomatoes) are 4 weeks old. They have:

-their cotelydons

- two stems (one from each side) which each have three leaves

- two stems just starting to come up from the center, each with three tiny leaves right now

I am going to transplant them into larger containers next week. After I do that, do I keep them until lights for 14-ish hours a day as I've been doing? Or can I start putting them in the (indoor) sunlight for 6-ish hours a day?