overstamping
Overstamping, in philately, is the practice of applying a newly printed overprint to an existing postage or revenue stamp after its original issue. Overprints are used to alter the stamp’s denomination, indicate a change in governing authority or territorial control, provide provisional or emergency usage, or convey commemorative, political, or propagandistic messages. They may be applied to stamps in a single color or multiple colors and can cover the full design or only part of it.
Overprints vary in technique and purpose. Value surcharges raise or lower the stamp’s face value to reflect
Collecting and authentication are important aspects of overstamped stamps. Because overprints can be forged or applied
In sum, overstamping is a common philatelic phenomenon reflecting administrative changes, wartime contingencies, and commemorative aims,