It sounds minor to me, but better to ask someone in Europe, familiar with EASA.
The regs are 23.1457 and 23.1459. Do these appear on your airplane's Basis of Certification ? No matter if they don't, your STC's Certification Plan can be based on the latest requirement (or possibly an earlier amendment). You need to discuss this with whoever in Europe is going to certify the STC (a DER or a EASA region office).
another day in paradise, or is paradise one day closer ?