"providers output existing cargo" checkbox option not respected for timed out trains

[Quezler]

Error message or bug description After trains time out due to a clog, those arriving (not shown in the picture, post-manually solved) can have signals of items that were in the inserter's hands inside the output combinator, requiring me to manually empty unwanted cargo for a while until the trains load properly again until the next clog, however many hours that might be, after which they would consistently dual-signal again.

To Reproduce

LTN version 1.18.6

[0ptera]

Needs more information, ideally a save with only LTN used with a station & train in that state.

[Quezler]

https://proxmox.nydus.app/optera/_autosave67.zip

here's the save file, to reproduce:

• from the middle train [gps=-39,-65,Nauvis Orbit] manually take out the iridium ingot (e.g. by grabbing half a stack of stone and swapping it with the iridium, so the inserters cannot put more iridium in that slot)
• from the train to the left of it, do the same thing with the 2 barrel stacks
• now another train will ride into the station you've cleared first
• notice how the output combinator has both iridium and stone in it, whilst the settings say that providers don't output their existing cargo

the file is 230mb and unfortunately contains a whole bunch of other mods too, but at least its from right before the issue happens and doesn't just contain a train already arrived with a wrong state.