My daughter is around18lbs and we use the V2 and 3 BG. I find the rise low on them but still use the middle poppers for a good, snug, leakproof fit. When I put the nappy on I always have to shuffle it about a bit and pull the tabs closer together a couple of times until I am happy. There are a couple of times when it has crossed my mind to go up to the next 'setting' but I remember reading somewhere that if you do that too soon then you will get leaks.
It does sound like you could do with moving back down even though you might think the nappy looks a little snug. It has a reputation for being a reliable nappy and you certainly shouldn't be getting leaks out of the back. The nappy is always really snug on my little oneand her tummy button exposed
Good luck with it... don't give up because they really are great nappies.
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