Updating calibre portable: downloading wrong install file

When my calibre portable installment informed me that there was a new calibre version available, I let it download the according new install-file.
Just before I was about to start the actual installation, I noticed that the downloaded file was not for a calibre portable version, but for the non-portable one, due to the missing "portable" indication in the file name. Manually downloading the portable installation corrected this mistake.

So, should calibre portable not refer to the "portable" download location instead of the normal calibre download location?