New firmware causes blf problem.

[chris_flexfone]

Hi

The BLF buttons are not provisioned in these cases. It is the case when we upgrade an old Yealink for instance an T46G typically from firmware version 28.75.0.45 and up to the new 28.80.0.70 firmware that all blank BLF buttons are turned into empty speeddial buttons - or at least so it seems in the web interface.
If we provision the buttons to blank value, they look correct. This is not an option for us however, as the customers who have chosen not to have the BLF buttons provisioned often will have manually set up some values, and as we have no way of knowing if an BLF button is empty or manually set up by the customer, we cannot just blank all BLF buttons that are not provisioned by us... Is there anyway this can be fixed, so that blank values remain blank after firmware upgrade, without provisioning them?