Freely-downloadable tracks for the PSP's first two Taiko no Tatsujin Portable titles have been openly shared with its players for a cumulative period of time that surpasses the decade, although it looks like this situation isn't going to last any longer.
The two notices above, available in the two games' respective websites, promptly inform that the DLC tracks will be removed from the official websites after January 31st. If you want to add the 40-or-so songs to your games before they're gone for good, you can check out one of our earliest guides on this blog, by following this link.
Credits to the Taiko no Tatsujin Discord user unknowwiiplayer for the find!