P: Post A Lr "Version Timeline"

This one should do the trick Steve https://helpx.adobe.com/lightroom/kb/lightroom-downloads.html

Or if it's installed Lightroom CC 2015 (go to Help menu > System Info to check the version number), then you can just add your serial number. https://helpx.adobe.com/lightroom/kb/serialize-lightroom-cc-trial-to-activate-as-lightroom-6.html?re...

I've just wasted an hour downloading the wrong version of Lightroom. Adobe are money grabbing $!@^£ all I want is what I bought standalone Lightroom. CC is too complicated and expensive for my simple needs.
I took great care trying to find the correct download, but when it finished it said that my subscription had expired. I knew my CC subscription had lapsed, because they increased the price by about £40 pa.
What a waste of effort, unfortunately I had to reset my laptop, which is wht LR no longer works.
Does anyone know how I can install the single payment LR that I paid for?

IMHO it's clear. 
Since CC 2018 "normal" Lightroom is Lightroom Classic CC, and a new, web based app was born as Lightroom CC. 
Well, I agree, that would be much better if they leave Lightroom as Lightroom and the new app was called Lightroom Net or something like that...  

Adobe has certainly (and deliberately?) confused things with its branding. A simple way to keep things straight in discussions is to use the version number shown in Help > System Info -- 5.7,6.14, 2015.12, 7.1 all unambiguously identify which version we're talking about.  Then we don't have to remember the label du jour that the marketers find so important.