According to Art. 15(2)(c)(i) RPBA 2020, the filing of new requests, facts, objections, arguments or evidence, as a rule, do not justify a change of date.
In J 4/03 the Legal Board held that the desire of an applicant to file unspecified new evidence at an unspecified future date could not amount to a serious reason for postponing oral proceedings. Even in ex parte proceedings the appellant had to attempt to file any facts or evidence he wished to rely on before the set date of oral proceedings so that the board could exercise its discretion under Art. 114(2) EPC 1973 whether to admit the further evidence or not, on the basis of the relevant material.
In T 881/95 the request for postponement was refused because the evidence, which could only have been provided later, was not such as to affect the decision.
In T 427/05 the appellant filed one new main and 71 new auxiliary requests approximately six weeks before the oral proceedings. The respondent (opponent) submitted that none of these requests should be admitted into the proceedings; they were late-filed and too voluminous. Failing that, the oral proceedings should be postponed. The board decided there was no reason to postpone the oral proceedings in view of its decision to admit only those late-filed requests which related (albeit narrowed down in some cases) to the subject-matter which had been central to the discussions from the outset.