check for updates on startup works only sometimes

Development Suggestions for the Arduino Project
1

Steps to reproduce:

You need a version of the arduino IDE that is not the latest available.

  1. Open the Arduino IDE
  2. A dialog warns you that an update is available and asks whether to download it. Say no.
  3. Close the Arduino IDE.
  4. Open it again

Expected: it should prompt about the update again.
Observed: it doesn't.

If I wait some days before I start Arduino again, then the prompt will appear again, but I have no idea of how much time has to elapse between restarts.

This may be expected behavior, but when will it check for updates again? Tomorrow? After the next reboot? How much time has to elapse between restarts to make it reasonable to check for updates again? If the user can't control nor know that, then there should be a menu item under Help or a button under Preferences to "check for updates now".