Firmware issue adding Kwikset Smartcode 914 lock

I'm having a problem connecting my Kwikset Smartcode 914 lock to my Xfinity Home system. I already had to swap it out as my first lock was an "Amazon Key Edition" with Amazon-customized Zigbee firmware; it apparently works with some generic Zigbee hubs, but Xfinity rejects it as invalid firmware. Now, I replaced it with a unit that's supposed to be generic Zigbee & compatible with Xfinity; I still get an invalid firmware message, but now it's only one character off from supported firmware (0x3071C40A instead of 0x3071C405). Is it possible that you missed a Kwikset firmware update & need to add this to your list of supported Kwikset firmwares?