I've been on HBC for the last ten years and I don't think my flow is heavy at all. I usually empty and clean the cup every morning, and it's never full.
Yesterday morning, after a day of menstruating, I had leaked a bit onto the bed during the night. When I removed the cup it was almost full, so I thought I'd just left it in too long before emptying, that it had spilled over. This morning I've leaked again. Removing the cup, there's almost nothing in it.
Insertion has never really been a problem. After the first few times using a DivaCup suction has worked. I don't leak during the day, and this has never really been a problem before. I've had one other leaky night, but only that one - before now.
Any tips are welcome! (Maybe this is my subconscious inserting the cup wrong because I can then persuade myself into getting the turquoise cup from LadyCup??? ;) )