Perhaps some one more expert on this situation could help you, but as I see it, it's way better to leave this untouched because you'll never know if there's something that went wrong with the compilation/build of the last kernel package that you download.
I can tell this myself, when I tried to install GNU+Linux-libre GuixSD on my personal computer and got a kernel panic in the automated build of the system kernel. On top of that, I forgot to learn how to tell GNU+Linux-libre GuixSD so as to make it's GRUB installation to look for other systems in other partitions, and I almost lost the ability to use my already working Trisquel installation and all my personal data. Luckly, I have my mother's computer which, despite running non-free software, allowed me to at least put a copy of Trisquel on a USB device to reinstall Trisquel's copy of GRUB. But I still haven't learned how to tell GuixSD's copy of GRUB how to recognize other operating systems. Besides, I have never done such manual work with GRUB. So, believe me or not, someday you'll thank yourself for keeping at least one older version of the kernel installed. :D Another example COULD BE (I'm not sure) that strange bug with applications using the Qt interface (which afected, for example, VLC and Mumble). Where, at least for me, updating to the latest kernel from Trisquel's repository solved the problem, that I was having with the previous version. Under that situation, I could also have selected the oldest entry related to Trisquel on the GRUB menu to see if the bug would persist, but I decided to update once again just to make sure, and so I was lucky. :D
