I'll quickly discuss my past experience with OINP in case it helps people make a decision whether to accept it or not. I entered the pool in Dec 2015 with 452 points. A few days later, I got a PT NOI from OINP, but because I was at 452 I decided to hold out and wait for the scores to come out early in the year. I missed the cutoff by 1 point twice, at 453. Super frustrating!!! Then I lost 5 points in March due to my birthday, and I also gambled the score would fall, and missed out on OINP. It took from Dec 2015, until Feb 2017 for me to get an ITA, and to be honest I feel lucky to have gotten another shot.
There are no guarantees that the scores will continue to fall, or that CIC won't change the rules on you in the middle of the game. I spent a lot of time during 2016 wishing I had took that OINP invite, and luckily I got another shot. If you get OINP, start getting docs ready in case scores don't fall so that you can submit them. Don't miss out on your opportunity because of what you think might happen. Sometimes when you don't take an opportunity, you don't get another shot, and it's gone for good.