Did you notice the plate number on the new Soda Fountain Favorites issue? It is in the middle of the pane of stamps, not in the corner.
Traditionally, plate blocks of rotary press printed stamps have a plate number in one or more corners. When the USPS moved to creating mini-panes of 20 stamps (instead of the traditional 50 or 100 subject pane of stamps), they added a plate number in all four corners.
This is not the first time plate numbers have appeared in the middle of the stamps. Many of the more recent “convertible” booklet issues (as the USPS calls them) have the plate number printed on the small selvedge that separates the panes. The USPS contends that customers can remove this small strip of selvedge, leaving just the backing paper. The booklet pane folds up into a smaller format that fits inside a wallet or purse.
However, as far as I know, this is the first time the plate number has appeared in the middle of a pane of sheet format stamps.
Because there are no die cuts in the paper, saving a plate block will require a little more effort. Collectors will have to use 10 of the stamps from the upper or lower half of the pane. Then use scissors to trim away the excess backing paper. This leaves the small strip of selvedge with the plate number and the adjoining strip of 10 stamps.