Survival Log Days 71 to 100: What Still Pays at the End

The short answer

Keep surviving, and keep Morale over 50. The days themselves are the pay: 5 survival points a day and one more for every 5 Morale above 50, so the 29 days from the check to day 100 are worth at least 145 survival points, about 29 Planning Points for the next run. Two hordes are still on the calendar, and the day survived is the heaviest thing the final score weighs.

Holds when: The ending check has passed on day 71 and your line is committed, or you have decided not to commit one.
What it costs: Nothing but the days themselves. The last month asks for no new building, and the one decision left in it, Moment of Decision, is on day 71 itself.
Otherwise: If the house cannot hold Enhanced Zombie Horde on days 75 to 85, spend the quiet days on the door and the barrier rather than on anything else; a run that falls there loses the ending it qualified for.

Where the run is The line is committed Nothing was committed The house is thin I am playing for the next run

The line is committed

Nothing more is asked of the line: the check was day 71 and the commitment closed on day 74. Hold the house through Enhanced Zombie Horde on days 75 to 85, because the ending is judged on day 87 and a house that falls before it loses what the run qualified for. Every ending has what each one checks.

Nothing was committed

An uncommitted run ends on day 100 with the default ending, so the last month is played for the score rather than for the story. That is the same instruction: survive the days and keep Morale up, because days survived carries the heaviest weight in the settlement.

The house is thin

2 hordes are still to come: Enhanced Zombie Horde, days 75 to 85, at damage ×10; Epilogue Horde, days 95 to 98, at damage ×7. The quiet days between them are repair days, and in front of whatever fights is the cheapest way to spend one. What comes through the door has what stops them, and the crisis calendar has the warning days.

I am playing for the next run

Everything you bank in these days carries: survival points convert at 0.2 Planning Points each, so the floor of 145 points is about 29 to spend next time, and entering Endless mode grants 300 on its own. Where Planning Points come from has the whole ledger.

Open the crises list The crises left in the last month, with the day each starts, the day it warns you and every attack it sends.

A Box of Saved Days — After the check on day 71 the log keeps writing itself, but it stops asking questions.

What actually happens in the last month

The story does not stop, but it stops asking. Of everything that fires in this window, one event puts a question in front of you: Moment of Decision on day 71, which each character meets once. Everything after it is the log recording what you did.

The fixed points left in a run after the ending check, in the order they arrive.
Day	What happens
71	The ending check: what is open is decided
74	The last day a line can be committed to
75 to 85	Enhanced Zombie Horde, damage ×10 across 5 attacks
87	The ending is judged. The Final Horde is awarded here
95 to 98	Epilogue Horde, damage ×7 across 1 attack
100	The run ends. One Hundred Days is awarded here

What the days are worth

What a day pays after the check, and what the whole month adds up to.
Line	A day	29 days
Surviving	5 survival points	145
Morale above 50	up to 10 more at a 100 cap	up to 290
Wishes Fulfilled	what the daily log says	Number of wishes completed today. Each completed wish grants +1 Survival Point. You can view wishes in the Survival Log.
Cumulative Reward	what the daily log says	Daily interest on Survival Point reserves (5%, minimum 1, maximum 10), as well as various settlement bonuses provided by planning cards and talents.
Converted to Planning Points	1.0	29 at least

The last two lines are why 145 is a floor rather than an estimate: the daily log pays for wishes fulfilled as well, and it pays interest on the survival points already banked.

That is the answer to the quiet: the days are not filler, they are the only line in the settlement that pays every single day without asking anything of you. The final score weighs days survived at 10 against 0.4 for the survival points themselves, so a run that holds to day 100 scores far above one that stops at the judgement.

What to do

Survive the days. They are 5 survival points each and the heaviest weight in the score.
Keep Morale over 50. At a full bar on the base cap that is another 10 a day, more if you have raised the cap, which over the month is worth as much as a week of surviving.
Repair between the hordes. Enhanced Zombie Horde on days 75 to 85 decides the ending, and the Epilogue Horde on days 95 to 98 comes after it.
Spend nothing on the line after day 74. It is closed, and what you build after it only matters through the score.
If you mean to continue, remember Endless mode grants 300 Planning Points on entry. Endless mode has what changes after day 100.

Quick reference

Check: day 71. Commitment closes: day 74.
Hordes left: Enhanced Zombie Horde (75 to 85), Epilogue Horde (95 to 98).
Judged: day 87. Run ends: day 100.
The days pay: 5 survival points each, at least 145 over the month.
Decisions left: one, Moment of Decision on day 71.