Thanks A-330-300, I did actually make the request when EI called me. It seems that because of the time-range, a six week trip falls outside the scope of a system-applied no-fee amendment. I was nonetheless told it could be done immediately, but in exchange for an additional €1000!
When I protested - also pleading that after a good experience last year, we'd converted to EI "J" from VS & BA - I was told a "case" would be compiled on my EI record(!), in readiness for my return call. As you suggest, I'm obviously hoping it's just a matter of an EI person having authority to waive the fee. We'll see how that goes, and I'll report back. That Irma's got a lot to answer for!