matio_svk if the period April - October suits you better than October - April you can also fly during that time as well (just skip once all flights after "her" requalification and start right after yours. Or you can take half your flights after her requalification and the other half after yours (and before hers). Wouldn't this work?
Now if you absolutely need common anniversaries then the "solution" I've seen posted here before was always downgrade/upgrade. That's, according to I believe every gold member who's posted this here, the only way to change the anniversary (unless of course Aegean grants either of you a 6-month extension, which in your case would probably have already been 12 months, so perhaps she could get a shorter extension if Aegean does indeed keep granting them?).