Unexpected behavior while using WebDAV with email address in login credentials

[wollomatic]

Brute Force Protection Version 1.2.0
Owncloud 10.12.0 (stable)

When using WebDAV and the Brute Force Protection App is Enabled, there is a different behaviour when I use an email address and password than when I use a username and password:

Using WebDAV with username + password:
Everything works as expected.

Using WebDAV with email address + password:
First, everything works as expected.
But then, after n requests, the brute force protection gets active, and I get a 401 status code.

Is Brute Force Protection identifying the correct WebDAV requests as a brute force attack when I use an email address instead of the username?