Which adjustment? Disable Stern lockdown bar button start

Which adjustment disables the lockdown bar button starting a game on a modern Stern?

I’ve looked through the manuals I’ve downloaded and noted the standard feature adjustments list on page 6 of most recent Stern manuals. If it’s there I’ve missed it.

Anyone know which adjustment it is? @Dwight
EDIT: Feature adjustment #51 on Jurassic Park. Could be different on other games.
Thanks for looking that up @fooflighter

Feature Adj 57 on Aerosmith