After an unsuccessful search I am left with a couple questions about an upcoming IAH-NRT-IAH trip.

I will be flying with my wife in July on CO 7/6 IAH-NRT-IAH (as part of the SEA-NRT B fare deal) and we have requested and already been waitlisted for the mileage upgrades to BF. The main question I have is, if in order to maximize our chances, I should split the PNRs? This is definitely what I would do for EUAs, but I do not know how it works for upgrade rewards.

Here is some extra data points: I am a OP Plat, and the miles are coming from my account. My wife is OP Silver, but I believe that should not matter since the miles are coming from a Plat account. Also, according to the agent at the OP Elite Desk, we are the first ones on the waitlist, and not a single seat has been sold in BF for our flights yet. We would not mind too much if only one of us (i.e. my wife) travels in BF.

I am just wondering if given that we are both in the same PNR, if CO were to open a single seat at a time, many other people on the waitlist might clear ahead of us...

Thanks for your insight!