Wait, I'm a little confused, here. So is it that you just had a 90 hour trip dropped due to your carryover? Won't there be a large number of trips available (that will show up tomorrow), that you can cherrypick for CIC? Many people do that purposefully. Sure, that sucks that you won't get any vacation pay that month, if I understand what you're saying---but do it right on your next vacation, and slide it to hit the max amount of trips.
We ALL learn the hard way. Even if we think we understood the contract, even if we clarified with futures, even if we talk to the experts. I just assume every time is going to be a worst case scenario, so plan my scheduling to deal with that!