I've build HAProxy 1.6.1 for Rawhide (Fedora 24), but I'm not currently planning to add this to Fedora 23. If there is enough interest, I will gladly provide HAProxy 1.6.1 packages for Fedora 23, but they will most likely not be pushed into the updates repository. Long story there.
Anyway, just wanted to let you know that builds are working and if there are any Fedora users that would like these packages, just send me an email. Cheers! Ryan