East China: Strange Misperforation

This East China 1949 'Victory is Huaihai' (SGB EC347) stamp is extremely common, so does not really warrant my interest (it's ugly too...), but this one really caught my attention.

What a strange misperforation. No part of the adjoining stamp or tab, for it seems only the right perforation went wrong. How could this have happened?
Will it have any value? Never seen a Chinese stamp before with such a strange misperforation, so the oddity-value should be high.

I suppose it's a line perforation, i.e. the horizontal and vertical perforation lines were done in separate operations hence the misalignment. I've no idea how you managed to make the left-hand stamp look banana shaped.

The paper of that stamp is so thin it curls up very easily... Probably some cigarette paper or the like. Thanks for the explanation!