I went through same thing many years ago, under JAR. The UK CAA were quite responsive to getting my Medical back.
Although UK no longer in EASA they do follow the rules very closely so their information may be helpful, it doesn`t seem to have changed in quite some time
www.caa.co.uk/media/y2nnuzsm/sleep-apnoea-fc.pdf
I have subsequently moved my Medical to another EASA State and I submit a CPAP report to the AME, at my medical.