Heres the scenario:
I have 2 L2 access switches dual homed to 2 distros.
Im running pvst+, uplinkfast, and backbonefast.
Timers are: 15 FDelay and 20 MAge
For a given vlan, all trunk ports on the access and distros are forwarding except for 1 on the distro. This is normal, of course.
When I fail one of the forwarding trunk links, it takes 30 sec to for that port to start forwarding. In other word, uplinkfast isnt doing anything.