(1) Subject to section 100 of the Act of 2019 and subsection (1A)(b), the court shall, in assessing damages in a personal injuries action commenced on or after the date on which section 99 of that Act comes into operation -

(a) have regard to the personal injuries guidelines (within the meaning of that Act) in force, and

(b) where it departs from those guidelines, state the reasons for such departure in giving its decision.

(1A) The court shall have regard to the Book of Quantum in assessing damages in a personal injuries action where the action is commenced -

(a) before the date on which section 99 of the Act of 2019 comes into operation, or

(b) on or after the date on which that section comes into operation in relation to a relevant claim where -