Ok super old thread - but did not seem to reach a conclusion, so thought I'd add some info based on my experience enabling the Line Lock app on a 2019 Bullitt RHD / Australian delivered car.
1. Get FORScan software on a laptop and enable the free trial extended license or buy one - I used...
Old thread I know - but just thought I would update based on my experience following this procedure with a 2019 Bullitt RHD (Australian delivered), which had about a 5% speedo error (speedo reading faster than GPS speed) - which was bugging me.
Summary: worked a treat!
* Bought FORScan...