I am measuring that looking at several send-outs. I look at the delivery logs (I tried to look at the "Delivery throughput" first but it is not working) and then i look at the distribution of values of @eventDate. Alright thanks, I'll check with them too!

Hello and thanks for answering. The Mail Rule Sets seems set correctly (as standard). I don't have any delivery priority unfortunately, i really don't know why (see screenshot). We do have the heatmap and yes we are running many workflows, sometime we are running too much at the same time and we are looking into that too. But when i look at some previous deliveries where we sent 100+k emails (without waves or Wait nodes) i see that during late evenings/nights the volumes increase from 7-8k per h...