The DODI-R... ( likely a typo, and actually referring to the DLC releases) has been actively releasing new content for the game, including new stages, characters, and game modes. This has helped to keep the game fresh and exciting, even for players who have already completed the main game.
This post highlights the features and content included in the Sonic Mania Plus v1.05.0713 Sonic Mania Plus -v 1.05.0713 DLC - - -DODI-R...
Sonic Mania Plus v1.05.0713 update, also known as the Encore DLC The DODI-R