Joined Cases C-439/18 and C-472/18: Order of the Court (Seventh Chamber) of 15 October 2019 (requests for a preliminary ruling from the Tribunal Superior de Justicia de Galicia — Spain) — OH (C-439/18), ER (C-472/18) v Agencia Estatal de la Administración Tributaria (AEAT) (Reference for a preliminary ruling — Social policy — Directive 97/81/EC — Framework Agreement on part-time work — Clause 4 — Male and female workers — Principle of equal opportunities and equal treatment of men and women in matters of employment and occupation — Directive 2006/54/EC — Article 14(1) — Vertical part-time worker — Recognition of length of service — Method of calculation of three-yearly length-of-service increments — Exclusion of periods not worked)