So you do have a pause event enabled? You need to disable it (not remove the code itself, use the toggle) if you want the program to stop immediately. I’ve explained why in another post but the short is with a pause event, we stop sending gcode but don’t hold until the event runs because otherwise there would be no way to send the pause event itself.
This is probably more noticeable on SLB due to the increased buffer size and is likely a feature we’ll have to revisit to see if it’s worth keeping.