Conditional format table based on 2 columns & lock hide old data rows but allow new rows

Hi

I have a table of private info that I would like someone to work on. Basically they need to add new rows of new unique venues completing all columns.

Firstly I want the row 11 and onwards to change colour if the text in column a and b both contain duplicates ie in the attached example row 11 would appear in a different colour as it contains both birmingham and roadhouse even though its doesnt contain the full duplicate " The Roadhouse".

Secondly I want to lock and hide all previous data ie rows 2- 10 so the user can only see there own entries but still be alerted by conditional formatting if their entry is a duplicate or not

CDan anyone help - having difficulty attaching the doc?

Dave

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