This server is at https://tagaya.wup.shop.nintendo.net.
The tagaya server provides version lists for Wii U titles.
You might also be interested in the Nintendo Switch version of the Tagaya server.
| URL |
|---|
/tagaya/versionlist |
/tagaya/versionlist/<region>/<country>/latest_version |
/tagaya/versionlist/<device_id>/<region>/<country>/latest_version |