Alcohol and breastfeeding, without the panic
This is one of the questions people are most anxious about and least likely to ask out loud, so here is the plain version.
Alcohol goes into milk, and comes back out again
Alcohol moves freely between your bloodstream and your milk. That means the concentration in your milk rises and falls roughly in step with the concentration in your blood. It isn't stored, and it doesn't build up in the breast. As your liver clears the alcohol from your blood, the level in your milk comes down with it.
That single fact answers most of the questions people have.
Pumping and dumping doesn't do what people think
If milk in the breast is constantly exchanging with your blood, then throwing it away doesn't remove anything, the milk that replaces it simply matches whatever is in your blood at that moment. The only thing that lowers the level in your milk is time.
Expressing is still worth doing for other reasons: if your breasts are uncomfortably full, if you need to keep your supply up, or if you want a stored bottle ready. Just not as a way of speeding anything up.
The genuinely useful version of that plan is the other way round: express before you drink, so there's a bottle for the next feed.
So how long?
The general advice for an occasional drink is to leave roughly two hours after a single standard drink before feeding, and proportionally longer if you've had more than one. That's a rule of thumb rather than a guarantee, how quickly you clear alcohol depends on your size, whether you've eaten, and simple individual variation.
The broad position taken by most health services is that an occasional drink is compatible with breastfeeding as long as you leave enough time. Regular or heavy drinking is a different conversation, and one worth having with a doctor.
What a test strip can and can't tell you
A milk alcohol strip reads one sample at one moment. It detects alcohol above a threshold, which means a clear result tells you the sample was below that threshold, not that there is definitely nothing there, and not that anyone has cleared you to feed.
Treat it as a piece of reassurance sitting alongside the timing advice, not as a verdict that replaces it. We sell these strips, and that's still what we'd say about them.
The part that isn't about milk at all
If you've been drinking enough to be impaired, the risk to your baby is your care, not your milk. Don't co-sleep or fall asleep on a sofa with your baby after drinking, and make sure a sober adult can take over. This holds regardless of how long you've waited or what any strip says.
And if you're worried about how much you're drinking, or you find you need a drink to get through the day, please tell a doctor or health visitor. That is a common thing to need help with in the first year, and it's help worth asking for.