Just be careful that you take the flyer giving the $300 obc home with you - I needed this to send to the agent at O who was insisting I would lose it if my booking was price matched to the new sale!
In the end the booking was changed to the new price with the $300 intact but I had to keep insisting that she spoke with her manager- It did help that I had a copy of the flyer from my room also quoting best price until sailing date , to send to her!