I was asking the support via eMail if it's working as is supposed to, and as I explained how my character was kicked out during the campaign, and had to pay for the next 30 days, re-activating them manually, they mentioned that:
The Final Fantasy XI subscription used to work backward and be paid at the end of the month. In order to re-activation your POL ID, you were asked to clear the old unpaid fees. The "Vana'diel Experience Campaign" is free and won't have to pay anything else until further notice.
It seems as if they were thinking it is an older account, but as I explained (again) that it was still active until then, and that I had to pay for it again, they took that as a 'issue was solved' somehow...
I should like to see some elaboration from the Community Representatives over here as well, as I do have other matters to attend to. In particular, are accounts/Content IDs that get cancelled during (not before) the event eligible or not?