I'm wondering how this will play out....

I had a flight booked VIE-AMS, but they cancelled it, along with the same flight on the following day. I know that EU261 obliges easyJet to offer alternative flights (the website only offers their flights) or a refund, but it also states that they should offer to rebook on another airline if they don't have any alternatives. I've been pushing this point with them for the last day (via Twitter) but they keep telling me to book the flight myself and request a reimbursement if they have no other flights within 24 hours. The thing is, there are no flights until 2 days later with them, but there is a flight on the previous night of the cancelled one.

Does anyone know if the 'within 24 hours' means after the originally booked flight, or can they claim it also means before?

I don't want to book a 100 EUR Austrian flight if they're not going to give my the money back!