My kernel: Linux raspberry 4.9.70-v7+
Command "BRANCH=next JUST_CHECK=1 rpi-update" gives the message "Firmware downgrade requested". I think function "compare_hashes" just checks on dates. Shouldn't it check on dates AND version?
Regarding the date, latest 4.14 in branch "next" ist older than latest 4.9 in branch "master". So a date only compare makes no sense here...
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[Started this accidentally @rpi-firmware...]