Hmm . . . interesting info. Didn't realize the 10 minutes would make such an effect on the IBUs. I'll have to learn to do the math on that, though hopefully not under a time crunch!
I was trying to save some since the original recipe called for aroma hops.
If it was an IPA, I'd be more worried; there are worse things out there than a malty porter. Once more, learning has occurred through buffoonery. I'll be sure to post how it tastes.