Mercurial push limit is indicated wrongly

When trying to push a Mercurial repo with 30 new bookmarks I get the following error:

#!python

remote: Push throttled (max allowable rate: 30 per 60 seconds).

The same push used to work before but now fails. As it turns out the actual limit is at 29 bookmarks in a single push so please either change the throttle response or fix the limit.

This happens on our Git-hg Mirror service so initially I thought it has to do with multiple pushes happening at the same time on a given machine, but no, the number of bookmarks in a single push is indeed the cause.