1. This Section applies to:
(a) payment transactions in euro;
(b) national payment transactions in the currency of the Member State outside the euro area;
(c) payment transactions involving only one currency conversion between the euro and the currency of a Member State outside the euro area, provided that the required currency conversion is carried out in the Member State outside the euro area concerned and, in the case of cross-border payment transactions, the cross-border transfer takes place in euro.
2. This Section applies to payment transactions not referred to in the paragraph 1, unless otherwise agreed between the payment service user and the payment service provider, with the exception of Article 87, which is not at the disposal of the parties. However, if the payment service user and the payment service provider agree on a longer period than that set in Article 83, for intra-Union payment transactions, that longer period shall not exceed 4 business days following the time of receipt as referred to in Article 78.