Hi perf12,
If I understand iStamp's posts about this overprinted one kopek stamp:
First, he asked about the possibility of an inverted background on this stamp.
Then, in his next post, he answered his own question by pointing out that if there were an inverted background on this stamp it would appear as a blank area in the shape of a crown at the bottom of the stamp.
There's a nice example of such an inverted background in the first lot, #418, on the Cherrystone link that you gave:
https://www.cherrystoneauctions.com...20&pagenum=1 br /
This Cherrystone example is clearly a different stamp but the basic design is the same.