Derogations from the provisions of Rule 4(1) are permitted, and these are at the discretion of the EPO. Clearly such permission must depend on the circumstances of the individual case. It may, for example, be envisaged that parties are unable to give one month's notice through no fault of their own, and, although they have made arrangements for an interpreter, the latter is unable (e.g. through illness) to attend. If, in such circumstances, the EPO is unable to provide for interpreting, it postpones the oral proceedings if they occur at the examination stage. However, in opposition proceedings, the oral proceedings continue if the parties agree and the employees of the EPO involved in the proceedings can cope with the language. In other cases, the EPO postpones the oral proceedings and any costs incurred by the innocent party as a result of the postponement are a matter for apportionment under Art. 104.