I finally got through to a call center, hard to understand, however, since it was certainly India-based. The summary was that there was a schedule change and, as a result, the partner airline offered the chance to cancel the flight for a refund (although I never received a communication about this) and the this was the refund center's way of asking if I wanted a refund.

They also noted during the call that the return segment of my flight, which I reserved in October, has still not been ticketed, but they reassured me that it is currently in the queue for ticketing. I have a feeling that I'll need to follow up on this one.