First of all, THANK YOU everyone for all of the information on this thread. It's been very helpful in terms of sorting out the details of EU 261.

I contacted BA about a recent long-haul cancellation and they informed me that they would compensate me for the occurrence.

This may be very clear to everyone, but not to me, but is this compensation in addition to, or in place of the "duty to care?" In other words, should I also try to pursue reimbursement for the hotel in addition to the EU 261 compensation?

My hotel (in central London) was expensive, so the compensation under EU 261 would just about cover it.

Thanks!