The Commission shall review this Regulation in the light of technological progress no later than five years after its entry into force. The review shall in particular assess any significant changes in the market shares of various types of heaters related to the labels set out in points 1.2. and 2.2. of Annex III, the feasibility and usefulness of indicating heater efficiency other than heat pump efficiency based on standardised heating seasons, the appropriateness of the package fiches and labels set out in points 3 and 4 of Annex III and points 5 and 6 of Annex IV, and the appropriateness of including passive flue heat recovery devices in the scope of this Regulation.