You can change a 2486DWH6 in to a 2486DWH8, or vice verse, by replacing the front cover plate with a new 6 or 8 button plate and reprogram it. 

Changing to 6-Button Configuration

• Replace the 8-button plate with the 6-button plate - Attach the change-out plate to the switch body by aligning the tabs and snapping into place
• Gently pull the Set button out as far as it will go
• Wait 10 seconds
• While simultaneously holding the On and Off buttons, carefully push the Set button back in, flush with the trim frame
• Once the Set button is pushed in, continue holding the On and Off buttons for 3 seconds, and then release KeypadLinc will (Beep) KeypadLinc is now in 6 Button Mode
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Changing to 8-Button Configuration

• Replace the 6-button plate with the 8-button plate - Attach the change-out plate to the switch body by aligning the tabs and snapping into place
• Gently pull the Set button out as far as it will go
• Wait 10 seconds
• While simultaneously holding the On/Off (upper left-most) button and the H button, carefully press the Set button back in flush with the trim frame
• Once the Set button is pushed in, continue holding the On/Off button and H buttons for 3 seconds, and then release KeypadLinc will (Beep) KeypadLinc is now in 8 Button Mode Page