My diary says “Wigmore Hall” for that Sunday, but no further details and (most unusually) no programme in my collection.
Further, we went off crack of dawn the next morning as we were due to take an early flight the to Barcelona – even in those days I don’t think we booked up stuff so tight.
So my guess is that we attempted to book that concert but didn’t get the seats we wanted; then planned our trip to Barcelona accordingly.
But if by any chance we did see this concert, it is written up very nicely on Intermezzo – here.