Android sdk updates come from google. if you used any nuget packages, they are updated by the developer. an SDK Update may require an update to the Maui sdk. .net runtime updates are released on the second Tuesday of the month.
Visual Studio is pretty good at notifying if an update is available. You should come up with you own release cycle. Weekly (if active development) or monthly, but you can probably get away with every 90 or 120 days.
The exception will be the release of a new Android version (typically yearly). You will want to test your released app on the pre-release o/s to determine any issues. especially after the final release. You will want to fix with your current code base and api version. Maui support of a new api release will typically come after the final release. Nuget packages may take longer (or may never be updated).