it happened with me with with kubuntu 20.04.2.0 fresh install
the problem first appeared during installing the first upgrades after OS installlation during the installation of linux 5.11.0-25 it showed me the same message that is in bug description
such as
"update-initramfs: Generating /boot/initrd.img-5.11.0-25-generic
Possible missing firmware /lib/firmware/i915/skl_guc_49.0.1.bin for module i915"
etc...
remember this happened after fresh install first update.
it happened with me with with kubuntu 20.04.2.0 fresh install
the problem first appeared during installing the first upgrades after OS installlation during the installation of linux 5.11.0-25 it showed me the same message that is in bug description
such as
"update-initramfs: Generating /boot/initrd. img-5.11. 0-25-generic i915/skl_ guc_49. 0.1.bin for module i915"
Possible missing firmware /lib/firmware/
etc...
remember this happened after fresh install first update.