They usually give you a date when they will contact you by (under the 'my submissions' section on your heartsy account), and in my own experience it has always been exactly on that date that I have heard back from them.
I believe they keep submissions up for vote until shortly before the feature, I think it's so voters get notified for a submission they voted 'yes definitely' for being featured, that's probably why the same shop you voted for was featured later that week.
Good luck to you! :)