When do I transplant seedlings from starter plugs

Ok so this is my first indoor grow, I have grown outdoors for years.. Also my first grow in coco, love that stuff, anywho I ordered some seeds, paid pretty good bit for them so treating like gold lol, I have had 100% germination rate starting my seeds in coco plugs placed in heated germination station, now I dont know when to transplant my new babies, they have sprouted true leaves and roots are coming out the bottom of the plugs so I lined my seedling tray with coco and have them all sitting in that under cfl, I will be transplanting into 3 gallon coco bags, they are auto flowers so dont wanna transplant again, once transplanted they will be going under a 1000w mh, dimmable so I can start them at 500w.. When should I do this, the oldest seedlings are all under a week and have one set true leaves, are they ready for planting into final pot and 500w of mh?

I would suggest transplanting them into a small container, like a red solo beer cup, so the root system can expand in that and allow for there to be a denser root system once it is in the 3 gallon bags. Roots tend to search down and outwards and take up the edge of containers more so than the center of the medium mass. Also having a better established canopy would do them good under a HID lamp.

I have always read to start auto flowers in their final pot being they really don't veg.. I would rather start in smaller pots for the same reasons u mentioned but being I dont wanna worry transplanting so many I am gonna do as the auto breeders recommend.. My worry is how long I should leave them in the coco plugs, many of them have an inch or more of roots growing from the plugs but they are very young, only one set of true leaves and some with only seedling leaves, I have some coco in the bottom of the seedling tray for the roots to grow down in to but the tray is packed, just dont want to damage any roots or have them tangle together.. But also dont wanna shock my seedlings if they are not ready to come out the tray, I don't have the dome on the tray but do have the heat mat under it.. Also not sure when they are ready to go from the cfls to mh, was thinking I would put them under some larger cfls then after they become accustom to their new pots put em under the mh

Ah, I didn't know they were autos. If their roots are coming out of the plug it is time to put them in their final pot. Roots won't fair too well in the open air like that, and since they're autos the plant, roots included, will only grow to a limited extent.