Comment 7 for bug 1760138

So we've noted several performance issues around leadership that have been fixed in or around 2.5.1. (moving to raft for leadership, and fixing performance issues around some of the lease update operations as the number of leases gets large.)
Given those fixes, it is likely that *this* bug was around "is-leader => leader-set" was taking longer than 30s to refresh its leadership, causing it to lose its leadership in that time, and thus we believe those issues to be fixed.
Not directly in 2.5.8, but as a close approximation.