EBU Single Rulebook Q&A 10 May 2023 2023_6798 Use of the last available data for risk quantification sample

Given the requirements of Articles 179(1)(a) and 175(4)(b) CRR, in case of a model development, should the last available one-year snapshot be used for risk quantification purposes (i.e., for the computation of the long-run average default rate) or be set aside for out-of-time validation tests?