East India Postage 1A Scott #12, Question On Cancellation.

Hello all Stamp Masters,
Its been a while since I looked over my stamps and I found this interesting piece which brought up the following question:

There is a regular cancellation but also a separate cancellation with the word "Stamped".

This "Stamped" Cancellation, is it in any way special?
I have never seen it before, and it does not seem to be part of the regular cancellation.

At first I thought it was an overprint, but then noticed that it extends onto the stationary.

Have you ever come across something like this?
I could not find anything on this at first glance.

@perf12
That thread talks of handwriting the word "Stamped" onto the stamps.

This one looks to be stamped onto it though.
Is there any difference?

It's the same thing,handwritten or stamped.
'Stamped' exiists in different sizes