I don't. Weather forecasts can be wrong, but sunset forecasts can't.
As always, it depends on the mission profile.
Sunset forecasts are usually quite reliable, but our flight execution might not. Examples, if the credit card system at re-fueling f*cks up and instead of a 30 minutes stop you end up in a 2 hours delay, if the taxi to the airfield gets stuck in a traffic jam, if unexpected weather detours you by a significant time, if the girlfriend you met needs a second helping, if you have to wait 45 minutes at the taxiway before the airliner gets off the runway, if if if.
There are hundreds of reasons why you could end up in a situation where a night rating relaxes.