The monitor layout went back by itself
A monitor layout RigReady applies is on probation until you have kept it once. A question appears, a countdown runs, and if nobody answers, the previous arrangement comes back by itself. This is what saves you when the new arrangement leaves you looking at a dark screen.
The countdown
After a layout is applied on the Monitors page or from the command palette, a dialog asks Keep this monitor layout? and counts down: Keep it keeps it, Go back reverts at once, and no answer puts the previous arrangement back when the countdown ends. The time is the Monitor layout revert timer in Settings, 15 seconds by default, and at least 60 seconds when an AI assistant asked for the change. The prompt, and why it is there, are described under Keep it or go back.
A fix on the Play screen, Make ready and Stand down ask the same question the first time they use a layout on this PC. Once you have kept it, with the same monitors connected, they apply it without asking; Replace with the monitors as they are now on the Monitors page counts as keeping it. They ask again after the layout is edited, or after a monitor is added, removed or moved to another connector (When RigReady asks, and when it does not).
The Monitors page does not call a layout applied when it went back: it says, for example, ""Flying" was not kept. The monitors are back the way they were."
A layout that was kept is still a layout you can leave: Stand down returns to the desk layout, and the Monitors page can apply any saved layout.
A screen went dark
If the new layout switched off the screen you were looking at, or put the window somewhere you cannot see, do nothing. When the countdown ends the earlier layout comes back. If the earlier layout cannot be put back, RigReady reports "There is no earlier monitor layout to go back to" or the error Windows gave.
Make ready stops at the question
Make ready and Make ready and launch apply the setup's layout as one of their steps. When the layout was not kept on this PC before, they then wait for your answer. Nothing else happens until you keep it or go back, and the game is not launched; if you do not answer, the layout goes back and the run says so. Run Make ready again and answer the question. After you have kept it once, the same run goes through without the question.
Stand down went back to the game's layout
When Stand down runs by itself after the game closes, it applies the desk layout. If that layout has not been kept with the monitors connected now (often after swapping the flight gear for the racing gear), Stand down asks Keep this monitor layout?, and with nobody there the layout goes back. The screens then stay as the game left them, and Stand down says: "Desk monitor layout: The new monitor layout was not kept, so the previous one is back. Next time, stay for the question and press Keep it."
The countdown before it warns you: "The desk layout "Desk" has not been kept with these monitors yet. Stay and press Keep it when RigReady asks, or the monitors stay as they are." To put the desk layout back now, press Stand down and then Keep it. With these monitors it is not asked about again. See Stand down when the game closes.
"Put the earlier monitor layout back?"
The arrangement from before a change is written to disk before the change is made. If RigReady was closed, or crashed, or the PC was shut down while the question was still open, RigReady asks once at the next start: Put the earlier monitor layout back?, listing how the monitors were arranged before and when. Choose to put it back or to leave the monitors as they are; either way the question is not asked again. See If RigReady is closed during the countdown.
Nothing changed when the layout was applied
When the layout asked for is the one the monitors already have, there is nothing to apply and no countdown: "The monitors already match "Flying". Nothing was changed." A layout refused by Windows, for example a resolution a monitor does not support, is reported with the reason, and the monitors stay as they were.