I'm not totally sure about that, I'm a bit new to this. Most places seem to require that you seed for long enough to make the torrent pretty much self sustaining, i.e. enough seeds and peers for it not to matter if you're there or not. One thing that you might like to look at is seedboxes, they can do the seeding for you, even if you're not there. I found a couple of free ones the other day
sonicbit and
seedr might do for you, if your demands aren't too huge.