Given those are so old now, (18.1 pushing 6 years...), you're probably going to spend a lot more time trying to upgrade than if you just backed up your /home directory and reinstalled everything, then restore your /home directory.

IMO LTS distros are meant more for commercial-type applications where you're going to install the operating system once and it's going to last the realistic lifetime of the system, and when you need to upgrade you're going to setup an entirely new system, or for atomic systems like containers where you can have a stable base and only have to update it once every few years. Given the infrequency of Debian releases you could say that it also falls into the same category, but I've found Debian Testing and Sid to be fine in the past.

On Tue, Oct 31, 2023, at 10:20 PM, greg zegan via PLUG-discuss wrote:
> 
> Hello,
>   Get online with Mr. Ubuntu at the next PLUG meeting.
> He did great things for me on my two Debian systems that got messed up.
> thanks,
> Greg
> 
> On Friday, October 27, 2023 at 04:03:02 PM MST, joe--- via PLUG-discuss <plug-discuss@lists.phxlinux.org> wrote:
> 
> 
> PLUG Friends ... Need help updating:
> (I hate updates and updating!)
> 
> I have four (4) IBM/Lenovo Thinkpads with
> these versions of Linux Mint installed.
> 
> #1 T420 linux Mint version is 18.1 Serena
> #2 T430 linux Mint version is 18.1 Serena
> #3 T460 Linux Mint version is 20.1 Ulyssa
> #4 T530 Linux Mint version is 19.1 Tessa
> 
> #1 is my primary computer and it is the
> only one on which everything (mostly) works
> the way I want it to work ... although it
> has several problems because the OS cannot
> be updated.
> 
> Every week, I back up all of my data to
> the other three (3) and each of them have
> various deficiencies and need to be updated.
> 
> For more than a year, I tried to get #3 to
> work in all respects as well as #1, but I
> was unable to get four (4) virtual desktops
> to work with unique screen backgrounds on
> each one.
> 
> Now, #3 has developed problems because so many
> things that had been working fine, no longer
> work after I was coerced to do the latest update.
> 
> Among the problems, I got an error message that
> said there was some defective program somewhere
> on the system, and it said I should use some
> program to find which program was defective,
> but I cannot find how to do that.
> 
> I would be willing to pay someone (hopefully
> someone in the East Valley) to help me get this
> mess cleaned up and get all of my old Thinkpads
> working the way they once did before blank blank
> updates screwed up everything.
> 
> Joe@Actionline.com ~ 480-325-5055
> 855 South 77th Place
> East Mesa AZ
> ====
> 
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