...a freshly-rooted clone, and those look gorgeous!

The fact that you took those clippings just pre-flower is also great! They should have just enough time to veg up, before needing to go to flower mode.
For anything in veg, the prevailing wisdom seems to be 18/6 lighting.

Going 12/12 immediately actually doesn't help speed things up much, according to some people whose opinions I value...

Those lil' ones need either a bit more dirt now, or to be put into some kinda hydro solution asap... biggest mistake (imho) would be to ignore 'em for a few days... Don't ask me How I Know This They look like they're practically begging ya for some nice, fluffy, perlite-y soil

Keep up the good work, mon! And keep posting those great pix!