I have an X620 setup as a core to a LAN with X440-G2 switches on the edge. I have policy working at the switches - for example: when a IP Camera is plugged in, policy assigns VLAN 13 untagged to the port, When an AP is plugged in, policy assigns VLAN 80 untagged and 60 & 70 tagged, etc. That part is working.
The cameras are setup with static IP addresses and are reachable, but the APs (and other DHCP enabled devices) get the port configured correctly according to policy, but do not get DHCP addresses.
For ports that have static VLANs assigned - DHCP is working fine.
On a similar note: DHCP relay is working fine (except as listed above) but PXE booting is not working on any port static or dynamic. I figured I would mention this in case these issues are related.