Early Postmark On First Day Cover?

Hi All-

I came across this cover that had a little note that said April 20th cancel on a FDC and then the very next cover had an April 30th cancel date, so I'm not sure if this is common for FDC's to have different dates of cancel?

I am in no way an expert or huge collector of covers/FDCs so if the note wasn't there, I wouldn't have known either way.

Thanks for your help on this!

Neither of these are "official" first day cancels. If this strip was issued on April 30 then that is an unofficial first day cover. The cover cancelled on the earlier date is just a cover, nothing special.
One thing is strange - neither of the covers are completely cancelled. Both covers have most of the stamps mint!
The cover cancelled on the 20th was ten days too early. I believe these covers were contrived by the same person - they look too much alike.

Peter

The stamps are all canceled. Look a bit closer and you'll see a wavy line running through all the stamps.

This set was available at every post office in the country on the first day of issue. In order for this to happen, some post offices had to have gotten it early. While they are instructed not to release the stamps before the official first day, though obviously not everybody followed in the instructions in the memo.

The April 20th is a pre-first-day cover. There are collectors who collect these. They have a premium, but not a huge one.

The April 20 cancelled cover is being overthought. The CDS is a manual device, with slots for the insertion of appropriate dates. Someone simply set the slug incorrectly with a 20 instead of a 30.

The first day of issue for this was April 30, 1974. It is doubtful that anyone would have been able to get the stamps ten days early AND get it cancelled, but it has happened before.

Another explanation is that the canceller (the device which was used to cancel the stamps) was accidentally set to the wrong day and no one caught it. Here's a FDC from the 1934 National Parks Series with an impossible First Day date - the stamps had not even been printed at that point. What happened was that whoever set the date on the canceller, inserted "MAR" for "MAY" and no one caught it.