Off Scan clarifications

[GCoxCasey]

From reading the protocol specification 3.1 we believe off scan is expected to work as follows:

• There is no useful case where the device maybe off scan and the points are effectively on scan ?
• If a FD is set off scan then its points are effectively off scan (even if their scan flags are not modified)
• In this case if the FD sends an UP/configuration message then the device.scan flag would be false, the points scan flag would be unchanged.
• If a point is taken off scan before or after the device is taken off scan then putting the device back on scan would leave the point off scan (because it was explicitly put off scan)
• If an off scan point is put on scan whilst the device is still off scan, then the point is still effectively off scan due to the device being off scan.

If our assumptions are correct the documentation may benefit from a few sentences to make that more explicit for other vendors.
thanks