Changing MAC in EPM erases Custom Entries, resets to template

If you change the MAC address, like when you have to replace a bad phone, all custom programming and buttons are erased and its set to the template. I understand if I changed phone type or the template, but just changing the MAC address does it. I believe this is something new as in the past I do not remember it resetting the template back to default unless I specifically told it to, or changed template / phone type.