Iris wore a FF NN last night, boosted with a Babeco bamboo booster (another three layers of bamboo!) and the bed wasn't wet!
The nappy was still soaked to the tabs though. But her wool was only barely damp, so that's a massive improvement. I weighed that nappy this morning after taking it off her and have worked out that she pee'd 401 ml overnight.
That's nearly 14oz. No wonder we're struggling. So, armed with that info, I think I'm going to email Suzanne and see how much liquid a new WNNN holds. Otherwise, I'll see whether an XL in other brands can be modified to fit my skinny minnie. We definitely need the extra material.