Here's what I could research: What is the difference between the Walk-In and Drop-In?
The Drop-In is a shared space. It is a chance to come in on your own or with friends to learn more about different health and wellbeing topics and chat about things that are important to you. You can also access a 1:1 with a worker and even get a massage on a Friday! No over 21’s apart from our workers are allowed in the drop-in space. At the drop-in there are fun activities, a different theme each month as well as free juice and fruit.

The Walk-In is a chance to wait for your 1:1 with a worker in a quieter environment. You are welcome to come by yourself or come with an adult/ support worker or friend. You will be offered a drink while you wait and hopefully you will be seen straight away or soon after.

Para mí tiene sentido en el contexto de las consultas de lactancia, porque en muchos espacios hay "rondas" donde participan muchas madres con un moderador para que, además de recibir el asesoramiento que necesitan, se sientan contenidas por pares, si así lo desean. Soy madre y algunos temas (crianza, p. ej.) conviene charlarlos en consultas grupales, mientras que otros (como corregir la prendida del bebé al pecho) conviene manejarlos en una consulta individual.

Entiendo que, en cualquiera de los casos, se trata de consultas sin cita previa.