If your file is for the older title, Version 1.2.0 was a major content drop:
While both main Taiko titles on Switch have a "1.2.0" version, the updates brought significant features to both: TAIKONOTRFES-(USA)-NSwTcH-NSP-Update120-Ziperto...
This was the patch that originally introduced the online competitive battle mode to the game. If your file is for the older title, Version 1
Resolved an issue where loading screens could hang or stop if network communication was lost or the console entered sleep mode. " used for installing games
This is a "Nintendo Submission Package," used for installing games, updates, or DLC on the Switch.
Players could start earning points to unlock new player icons. Technical File Details
Taito Milestones 4 Switch NSP/XCI [UPDATE] Download - Ziperto