https://www.epo.org/en/service-support/faq/law-practice/list-professional-representatives-entry/i-have-passport-date

I have a passport but the date of expiry is quite soon. I don't have a new one yet as I am not going to travel for a while. Does it matter?

If your passport is still valid on the date on which we receive a valid request from you, it is sufficient for the purposes of the request.