OK, I'll answer my own question here.

We're flying to Maine for the eclipse. They have the best weather forecast along the path of totality in the entire US, surprisingly.

I booked our tickets yesterday (i.e. just 4 days before the elcipse!) for 10000 per person per direction, arriving into PWM on Sunday. Flights were about still about $125 each wya, so a redemption of about 1 cpm seemed really good to me.

But then I randomly looked again today. The exact same outbound itinerary into PWM is now only 5000 miles. Yet the cash price has gone up to $200! So I rebooked, and then cancelled and redeposited the original award.

I didn't even realize Frontier had 5000 mile awards.

So now there's 5 of us going to the elcipse for 15k frontier miles per person.