to be frank, i always find those pms of people asking for sub4subs to be rather rude in my personal opinion. Like it almost sends a message to me that I look desperate for subs or something and at the same time, i also find that those pms feel like those advertisements you get in the mail that you always throw out because you don’t want the credit card they’re trying to sell you or some shit.
if you want to gain more readers, there’s loads of threads that I see pumped out on a daily basis that say “promote your comic/novel” that you can try. I promise you that posting in those will get you further faster than convincing individual folks to sub4sub like a door to door sales person. I find this would be much more practical if your purpose is to reach those milestones.
and like @skicoak said, it’s not like sub4sub actually gives many subs to start with, so why all of a sudden is it practical to use it for getting 250 subs? Like be realistic here, you’re going to take a solid minute to convince that many to do it. Especially if your tactic is door to door salesman as i stated earlier. Even more especially taking into account the fact that if your sub4sub dood doesn’t like the thing they subbed to and find the notification of you updating your comic to be rather needless, they will unsub. This is two fold, if you have a lot of subs to manually keep track of, you will not notice who it was that unsubbed so you’ll find it annoying to figure out which sub4sub deal to unsub to if that’s the sort of game that you play in this deal making sort
sub4sub? I can really only say “No”