US First Flight Covers

Anyone else noticed a boost in the popularity of early US First Flight covers? I picked back up with my collecting after an absence of roughly 2 years, and was blown out of the water on a couple of Dutch Country Auction First Flight lots - they were estimated around $200, and ended at around $800 each (all internet bids, on unpictured lots). A 3rd lot of considerably less covers ended at $500, still several hundred over estimate. I had requested further information and was not made aware of anything that would have warranted THAT kind of bidding.

I then took a shot at a lot of 14 first flight covers on ebay (though I've been a member here for a couple of years, I won't post the link, so as to stay within the rules) and, again - my snipe didn't even get a chance to fire, as the lot ended well over $100. Yes, they were nice early covers, but in the past, I could pick up a lot of hundreds of early Roessler covers from sellers such as Roecy for a fraction of what I see much smaller lots of covers going for now.

Did I miss something? Has anyone else noticed a spike in the price of these, or am I just going senile and imagining it?

How early are these early air covers you mention?

The ebay covers were part of an exhibit that was broken up - which made me cringe a bit, I wish it had been sold intact - and the covers of interest were mid-1920's; the lot I attempted to bid on and another both broke $120, the rest of the lots were mostly recent material and went unsold at $20 or so each. I wasn't too shocked by that one, given the scarcity of a couple of the covers. The Dutch Country lots were a primarily FAM (1920's through 1950) of around 400 covers (Est. $100-125 SOLD for $800.00) and the other around 400 CAM and mixed air events late 1920's/30's (Est. $150-200 SOLD for $800.00).

jAX,
I've noticed some of it, I would pay 50cents a cover in a lot, know I'm lucky if I can get a lot for $1 a cover.

The happy ending to this is that the Dutch Country lots that I DID win came in today, and included several hundred - non-stated in the auction description - 1930's to 1950's first flight covers in one of the boxes. I got these lots for a real bargain, so feeling really happy that I didn't chase the other lots.

First flight cover collecting is like collecting FDC's - the interest goes up and down. I have over 2,000 of them and have yet to have studied each one. The nice thing about FFC's is that you can approach collecting them in various ways; by state, cam number, what stamp was used, signed versus unsigned, what is on the cachet, etc. etc. etc. .....