I have been feeding from one side, taking a burp break, then putting my baby back on that side until he slows down/ rarely swallows. He doesn't tend to let go voluntarily , but comes off easily (minimal suction, iyswim) once he's got to the desultory feeding stage. I then put him on the other side.
Over the last few days, I've noticed that when he starts feeding on the second side, the first starts leaking quite a bit.
Sorry for such a long post. What I wanted to know was, does the leaking mean I haven't actually emptied the stored milk? I presumed it'd got to the trickle only stage. Am I wrong? I don't want to swap sides too early, obviously.