I often take my family along on business.

I typically use miles to book their awards and then pay for mine matching their flights exactly.

But I find two things happen:

a) The award tickets are not so great (i.e. not non-stop, early/late flights etc.)
b) The price of these not so great tickets is ironically really large!

Did anyone else find this pattern?

Lately, I've noticed that after a flight slips/transitions off the award list the price to purchase it drops greatly.

For example, I booked red eye award tickets SFO to IAD for 12.5k miles but they cost $400 to purchase at the time.

Today I found the same tickets are now $200 but they now cost 24K miles!

Did anyone else find this pattern of United increasing/dropping paid ticket prices to match award inventory?