Certainly a few clues of an HG failure being mentioned 🤔

Its definitely not a vent it cap, so has been modified, looks like its a 20mm hole so per have they intended fitting a sensor. The vent to stop a vacuum will be either a 5mm hole on the side or the cap is manufactured to include a vent...

I assume the tailgate was functioning 100% before. So whoever did the work in replacing the tailgate would have left some pencil marks to aid realignment when fitting the replacement, something similar to bonnet and side doors removal and...

Have you read the Handbook ?

As already mentioned you will find the info in the owners handbook. Whit most modern cars theres two handbook, basic and the full on version which u have to download from LR via their app. Then look for the chapter ‘driving modes. Not a disco I...

I should have mentioned - it is a discovery sport. I didn't see a separate forum...