I started with a Debian Jessie distribution and have upgraded it from a 3.X kernel to 4.19 now. There are still things that are not fully working (broken packages etc). As I am going through cleanup I have found that currently running lsb_release -a gets me:
No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux 8.11 (jessie)
Release: 8.11
Codename: jessie
Would a proper Debian Kernel upgrade change the output of lsb_release?