Hello and welcome back to BW forums
Congratulations on the new arrivals too, how lovely.
I would recommend using their adjusted age for A times and developments, obviously all LOs are different anyway so there is always flexibility in the EASY routine based on what suits the individual, but in general I'd go with the adjusted age.
They are still super young, I wouldn't expect much at this point and if there is sleep right after feeds sometimes I think that is to be expected. As they get bigger you can gradually encourage a bit more A time between E and S.
I started the EASY routine with my own DS when he was 4-5 wks old and initially was just gently extending his E times and putting a little A between E and S. I followed cues rather than A times for sleep and this meant some A times were very long and some short but cue following seemed to work well for a young baby. I was also sleep training, gently, with some good days and some not so good, but I had a lot of time to put into it which I imagine you don't have with 3 LOs under the age of 3yo!
If it was me I'd do what you can to put them down for naps so they learn gradually to self sooth, but I would also keep expectations low and not beat yourself up about it if they nod off when being fed or need a few sling/pram naps either. I always think it is handy to have some pram naps for babies when there are other children who need to go out and about etc, my own refused to sleep in a pram as he was just not used to it which caused me some difficulty. You might decide to sleep train in a pram so that you can either stay home and they nap or go out and about and they can still nap.