Runing LibreELEC-MXQ-4K-Pro_2G.arm-9.2.8.6 when trying to update to LibreELEC-Generic_S905.arm-9.2.8.8.tar i get:
###Starting debugging shell for boot step: mount _storage…type exit to quit ###
*** Error in mount_storage: mount_commin: Could not mount LABEL=STORAGE ***
i updated before whit the tar files and didnt had this kind of error.
You did not write exactly what kind of device you have, nor whether the LE runs from an SD card or an eMMC. If you boot from an SD card, you should try a clean installation first (with the correct dtb) on another SD card to see if it boots at all.