Both Windows links on the download page are pointing to the same 1.3 GByte file. I downloaded both files from both links and they are the same file.
It’s the update from Cubase 10.0.0 to 10.5.0.
The 300 MB version for updating from 10.5.0 to 10.5.10 is not linked, it’s missing! So… no update available.
EDIT: I found that the correct file is available for download via the Steinberg Download Assistant.