EASA can issue an ETSOA (Euro-Technical Standard Order Authorization/Approval) for certain equipment design, to simplify installation authorization on an aircraft type design.
I found no notice of such an ETSOA expiring at a certain date or for a certain certification basis. Still, at some point regulations evolve and ETSOA'd equipment may stop meeting those regulations. How is this managed?
As an example: suppose a few years ago, an equipment was designed and manufactured as per some ETSO, and approved by EASA for that ETSO under a certification basis including the now obsolete DO-178B.
Now or in the near future, an aircraft manufacturer wants to use that equipment on a new aircraft type that is required to use the updated DO-178C. What would the aircraft and the equipment manufacturers have to deal with as extra certification work for that equipment? And in the case there is no extra work, how will the EASA deal with new regulations in the years to come?
(this question is not specifically targeted at EASA's ETSOAs: consider the same question for FAA's TSOAs and similar mechanisms in other countries)