I appreciate everyone's responses
Yes, I'm glad to know it now rather than later, and yes, I know there's a good thing/bad thing going on, as I was the recipient of the "good thing" last month when they unexpectedly gave us a 2AM closing, which will be a first for us, so I know it cuts both ways, and this time I'm on the bad thing side of it...
Here's my thing: The early entry CP is two-fold. 1) it allows you the empty Main Street experience, which is just about the coolest thing to me, and 2) it allows you to get a jump on the crowds so that you're first on the rides. (We were going to eat quickly and pay for our meal when we first got seated so that we could try to be first riders on Space Mountain, something we have yet to accomplish.)
So, if I keep the reservation as is, I'm told by a dining CM that they should allow us into the park 15 minutes prior (so, 7:45-ish) which will get me the empty Main Street experience (unless something happens like Donald-my hero...that really stinks, but I liked your ending outlook on it), but we miss out on being the first (or close to it) on any ride.
Bottom line: it's not a good thing in any way, shape, or form. But, I can try to figure out a solution that will give me some form of good from it. Right now, the options are not appealing to me at all, but I will sleep on it and perhaps things will look brighter tomorrow
I told my DH that we could just keep the reservation, get into the park and experience the empty Main Street, and then go ride Space Mountain and let our credit card be charged for the $28.95 pp (there's three of us), so that would be one really expensive Space Mountain ride (but I'd miss my French Puff Pastry, too!

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