I'm normally a DL loyalist, but a much better fare means that I'll be on CO for an upcoming trip to RDU. Right now, I'm booked into a middle seat on two of the legs and was curious as to if/when seats tend to open up as we approach flight time.

On DL, you can sometimes grab a new seat at T-5, 3, and 1 days (as Medallion upgrades clear) and then again two hours prior to departure (when remaining preferred seating opens for general use). Are there analogous timeframes on CO? Also, if I do OLCI, can I still change my seat at a kiosk?

Thanks in advance.