Indicate when a mission is about to timeout

[SembeiNorimaki]

I prefer doing missions during daytime, so if I arrive at night, I usually wait until daytime to start the mission.

Problem is, I don't know how much longer the mission will be available, so it happened to me to be waiting in patrol mode for daytime and suddenly the mission times out and disappears.

Would there be a way in the mission description to include until when it's available? Or even better, the mission marker to blink or change color when it's about to expire?

That way I can safely patrol next to it and if I cannot make it until daytime I force a night mission.

[Niewiem]

This is rather OXCE request than X-Com Files one

[Alex_D]

I open the save and look for "missionSites" entry, then expand and look for "secondsRemaining". 
The upside is in XCF the time is rather generous, like 268200 seconds, which is 3.10 days. That's more than enough to shift troops and materiel across bases and to buy some stuff.
At least there is plenty of time to choose to do the mission at night or day time.

[psavola]

The vanilla behaviour is that the target missions (except UFOs) don't disappear if you are targeting the site with any of your crafts even if the timer runs out. This allowed you to use various tricks (for example, a second very slow craft to delay the expiry) to delay the missions. This behaviour has been explicitly disabled in X-Com Files.

In addition the timers are usually very generous and they have a huge randomness range. For example the duration could be randomly selected as 100-200 hours. This is clearly intended to make the player unaware how long precisely the missions is going to be available (without cheating). Clearly the mod author would not want the OP behaviour in any case, and I also don't think OXCE devs would think this feature would be all that useful.