BOOTP on Juniper 4200 stack works one one subnet, not another

Question

I have a Juniper Stack that connects vlans 10,11 and 50. 10 is servers, 11 is desktops and 50 management. Bootp is redirecting DHCP requests to a AD box on 10.x just fine for 50 vlan, and worked well for the 11 vlan for a few days then just stopped. Now if I look in the statistics I see that lots of packets are getting dropped for the reason "Due to missing valid local address: 575"

More information such as packet captures are included on my post on the Juniper forums

I will give the switches a reboot this weekend, but as bootp is working for the 50 vlan I cant see why it wouldn't continue to work for the 11 vlan.

Config:

forwarding-options {
  helpers {
    bootp {
      description "Workstation/ Management Subnet DHCP";
      server 192.168.10.242;
      maximum-hop-count 4;
      interface {
        vlan.11;
        vlan.50;
     }
  }
}