I have a continuing mystery. Booked CPH-BOS-IND through SAS for this coming week. BOS-IND has a SAS flight number (codeshare) but is operated by Delta (Republic E75). For some reason, when I log into Delta with my Delta confirmation number to select seats, all seats are "x-ed" out. A dummy booking shows those seats wide open. Called DL - they are completely stumped. Could it have something to do with the codeshare + operated by Republic? I'm able to select seats on the return, which was booked into a DL flight number. Will seats be available at OLCI?