Device Types

I am using Opmanager 6. I did a network discovery. I then went and re-assign devices to their proper type. This worked for the majority of devices. I have a few though that will not list in the designated category. They remain in the original group. For example:

I have several Wireless basestations that were originally classified as switches. I have since changed the type to Wireless. Unfortunately, they still are listed in the Switches group. I have tried creating a new device type and queried the device for the OID. This hasn't changed anything.

Is there anything else I can try short of deleting those devices and re-adding them?