how to make ai stand in a waiting line to use a service?

Hello i am working on an rts style game right now
and i am having trouble with telling my ai to stand in line,
i have some arrows set in the service actor that tells them where exacly to stand but i cannot figure out how to have them actually work
my problem is that when they spawn the data does not update in real time so they will stand in line 1 instead of 2, and i tried having it update real time with an event tick and a delay but that just makes the ai repeat and they walk slowly and bugged out, as well as once 1 of the ais gets to service all the others will just exit for some reason?
can someone help me figure this out, this system should be procedural in a way so i can have other services that are a tiny bit different aka just instances of the original service, i shall be waiting for your reply kind folks! if posible i would like to keep things simple by using blueprints instead of the ai branch tree, but if i really must use the branch tree i am ok with that