I think it really doesn't matter if you keep the clones or the original seedplants as backups. Personal preference.
I plan to backup the clones and flower the original seedplants as they are just much further along and bigger and the clones can grow/veg while the seedplants flower. Once they finished flowering, I suppose the backup clones will be somewhere around where the original seedplants were when they entered flowering. At that point you could go for a second round or simply prune/trim back the backup clones until you were able to cure the harvest and sample it and make your selection.
I am not sure either way what is a good method, hence my asking
At the moment I simply topped all my seedplants and used the tops as clones.
They are about 4 days old now and I haven't seen a root stub yet. A few of the tops have drooped a bit, most are looking more or less like when I cut them. I noticed that some have continued to grow leaf mass though which is not so great as they are supposed to put their energy into the roots ...
Anyway, since I just now topped them, I figure I give them another up to 4 weeks to veg before flowering. If this round of clones won't root for some reason, that should give me enough time to try for a second batch.
Imho you can't veg too long (unless it makes you hit your ceiling during flowering) so I am in no rush atm.
What still gives me a bit of a headache is the fact that it takes a solid 1-2 months after harvest until I can make a solid judgement and selection.
Originally I wanted to move on to the next strain after finishing the grow and just keep the clone backups until I had time to select.
But it looks to me like that is just too many plants/too much space taken up and I will likely end up flowering the backup clones (after cloning them again) instead of going to the next strain while I wait for the cure and selection...
Reason being that if I keep say 30 backup clones, even if I prune and trim them to keep them in solo cups, and move on to popping another 30 seeds of the next strain to pheno hunt, I will have to clone that next strain while still not having made my selection on the first.
The plant numbers will just get too staggering for me. Spacewise I think I could manage but I know I would start feeling uncomfortable if I got significantly beyond 100 plants...
Let's see how things shake out though. I did plan all of this so long in theory and then when I first tried to put it into practice, I ruined my organic soil by adding bio canna boost and rhizotonic which lead to a massive fungus gnat infestation and severely crippled second grow. I wasn't able to root a single clone yet due to this.
So step by step I suppose. For now I need to get some rooted clones, then I can look further
/Edit
re: Flipping clones before rooted to sex them
Wow, I was not aware this is possible!!!
That seems like a game changer to me, honestly.
How would I go about that? Simply cut clones from each plant as usual, put them into jiffy peat pellets and just instead of waiting for roots, stick them under 12/12 and they will show tiny buds/pollen sacks?
That would be amazing because I could simply cut a second round of clones from the bottom of the plants (where I would defoliate them anyway before flower) and stick it under 12/12. That would safe me from re-potting/transplanting all those males into the larger flowering containers and having to remove them again once I learned their sex.
I suppose if this works as it does in my head, I wouldn't even have to bother with rooting hormone or cutting at 45° angle and all that. Just snip off a clone, stick it into some perlite or a jiffy peat pellet or something and throw it under 12/12 and within a few days I should know the sex, no?
I would've thought the "clones" would just die then but I suppose it makes sense that they would stay alive long enough to at least show their sex without a doubt.