1. Where the UK ETS authority informs the regulator under Article 15a(4)(b) that:

(a) a deemed application for free allocation in the 2021-2025 allocation period is valid, the regulator must calculate the preliminary annual number of allowances to be allocated in respect of the installation for each scheme year in the 2021-2025 allocation period;

(b) an application for free allocation in the 2026-2030 allocation period under Article 4 is valid, the regulator must calculate the preliminary annual number of allowances to be allocated in respect of the installation for each scheme year in the 2026-2030 allocation period.

2. For the purpose of the calculation referred to in paragraph 1, the regulator shall first determine the preliminary annual number of emission allowances allocated free of charge for each sub-installation separately, as follows:

(a) for product benchmark sub-installations, the preliminary annual number of emission allowances allocated free of charge for a given year shall correspond to the value of that product benchmark for the relevant allocation period set out in Annex 8 multiplied by the relevant product-related historical activity level;