This is just whatever comes off your nipple when you take them off
It's what hasn't been pulled in yet, I take them off leaning forward then decant straight away. Sometimes mine is what is still leaking out after the pump has turned off
It happens to me if the pump turns off and I wait 10 mins before emptying. I think my boob is still leaking when the pump is off. Started emptying it as soon as it turns off and haven’t had the problem since.
I’d love to know too. I have both Elvie and these pumps and I always have milk on the outside and it’s forever causing me to change bras etc. mine tends to “fall out” of the flange as I take it off no matter if I lean forward etc first