This could be an indication that you have the linux-meta package synced.
The console log presented does not contain any information on what you where trying to do when the message was displayed.
But you could try removing the meta packages… but without more information it will be a guess
sudo pacman -R linux-meta linux-acpi_call-meta
Not likely - it is still too early to deduce anything about the next LTS as listed on kernel.org. Manjaro follows kernel.org - but other distributions may choose another version for their long term support which is independent of kernel.org.