You might want to add a bit more pressure (which could turn into a torrent) by posting on the Lidl FaceBook page, just as is happening on the Aldi FB.
Usual questions:
Do they get a 'kick-back' from the PPC?
Does their contract wih the PPC give them authority to pursue through the courts?
Amount of grace period?
How does ANPR cameras manage such as Disabled bays and Parent and Toddler bays?
What does their planning permission say about free car parking provision?
Does their car park service other shops/outlets?
How does Lidl check that the ANPR cameras are accurately timing their customers entry/departure?
Ask them to explain how ANPR monitors parking as opposed to entry/departure?
That should keep them busy - but to focus their minds, why not copy the link to the Aldi FB page, here:
https://www.facebook.com/AldiUK?filter=2