Veg Stage Duration

Just a curious question: Once a plant is in its vegetative stage, (grown from a feminized seed in soil) is there a maximum time it can stay in that state?
reason I ask is because i was sittin here smokin some green crack and thinkin bout possibly starting a separate "mids department"(bag seeds) aside from my "name brand" strain-specific grow setup, simply to learn LST, HST, SCROG/SOG, etc methods, fetilizer usage and trimming/pruning techniques without the fear of killing a plant i paid for! But as they all would different flowering times and growth status', possible health issues, i was just gonna put them all in a single, larger veg tent and just keep em in there till a spot opened up in the flower tent, and just keep the veg tent stocked like a reservoir and just cycle em in and out. Keep a steady stream flowing of output.
I just wasnt sure if keepin them all in the veg state like that "until further notice" would effect the end result.
I get thats how mother plants are dealt with but i aint there yet so i aint looked into mother plants, clones and all that so i dont know if thats a thoughtless question or just a stoned question!
Thanks in advance.

you will run out of space, you ned to learn how to clone and keep your crop going that way, by relacing the flowered ones with new clones

The problem I've had trying to veg for prolonged periods is that the plants outgrew the containers.
Like go-go suggested, once you've found a keeper, start a mother and take cuttings from that.
I tend to cycle my mothers through the flower tent after a few months.

Not sure what these guys are smoking but if you remove 50-80% of the plant every week or two as needed, you can keep them small basically forever. They might end up looking kinda crazy though.

A root prune with fresh soil ever 4-5 months plus the usual foliage pruning will keep a plant going for years.

You don't need cannabis plants to experiment with techniques. I learned a lot from jade plants in the past couple years.

My first (and only) grafting was with tomatoes. Layering, too.

As for the veg times, I've always wanted to veg a plant for a year or more and then flower it. I currently have a tight internode indica-dom that I expect to veg for at least 4 months.