Plan around the Moon, not just its phase.
Pick the dates from geometry, then check the weather when it gets close. The dark window moves about fifty minutes later each night, and the usable moonless stretch collapses to nothing around full moon.
Move through a lunation.
Pick a phase or play the month. The most useful dark hours migrate from morning to evening as the Moon moves east.
New Moon
The whole astronomical night is available for faint targets.
Why moonrise slips
The moon moves roughly 12 to 13 degrees eastward against the stars each day as it travels its orbit. The Earth turns 15 degrees an hour, so it needs about fifty extra minutes of rotation to bring the moon back into view — which is the origin of the familiar rule that moonrise slips about fifty minutes later each day.
Which half of night stays dark
That steady slippage is what shifts the relationship between moonlight and darkness through the month. Around new moon the whole night is available. Through the waxing half the moon dominates the evening and clears out before dawn. After full it does the reverse and takes the morning.
That means "dark hours" is not a property of the date alone — it depends on which half of the night you can actually be out for. Someone who can only observe before midnight has a completely different good-nights calendar from someone who can stay until dawn.
Turn geometry into dates
The moonless night planner draws all of this as a strip, one row per night, with astronomical darkness unshaded and the qualifying window bracketed inside it. Filter it by how much continuous darkness you need and how much moon you will tolerate, and the shape of the coming month is obvious at a glance.