For precise early assignments, I believe you would restart, then framestep. This will pause because all Lix framesteps pause. Then it doesn't matter whether the restart paused or not. Since Proxima considered an NL issue report towards restarst-keeps-pause, there is a mismatch between my reasoning and Proxima's. Where would that be? Does the NL framestep pause?
NL framesteps do not pause, which is good for two reasons that don't apply to Lix:
NL lacks builder-queuing, so to do a long bridge, the usual technique is click, skip 10sec, click, skip 10sec....
NL lacks turbo-fast-forward, so after assigning, if the next time I need to assign is some way off but I'm not sure whether a 10sec skip will go past it, I skip 2sec a few times.