Most of the KEYone releases are being updated to Oreo (which is probably the last OS update this phone is going to get), but not all of them. Sprint, a North American carrier, has confirmed that it's KEYone variant will not be receiving the update. The exact reason why is unknown. Other US carriers may or may not upgrade their KEYone's OS' accordingly.

LineageOS 15.1 Oreo is now available for a number of smartphones

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