You are able to inactively progress up until 99% of your highest stage reached. For example, if your max stage is 1000, you can progress inactively until stage 990. This works similarly with tournaments, but instead of 99% of your actual max stage, it will look at your tournament max stage. This means you cannot inactively increase your tournament max stage.
Inactive progression will start after five minutes of inactivity, so you’ll want to ensure your game stays closed until you’re ready to start playing again. This five-minute cooldown will reapply every time you open your game.
The most common reasons you are not progressing while you are away from the game are:
You are above your Silent March max stage
You are on the first run of a tournament
You are above your tournament Silent March max stage. Reminder: instead of your usual Silent March max stage, it will look at your current tournament max stage
If you would like a deeper dive into Silent March, lemmingllama has a great guide that explains all of the mechanics in depth. Check it out here!