Handwritten I.r. On Great Britain Scott #68 ... Meaningful?

Hi Everyone,

I have a plate 20 variety of Great Britain Scott #68. It has a handwritten I.R. clearly underneath the cancel. I find this very strange since this design is not one of the I.R. OFFICIAL stamps. Curious to hear thoughts about this.

Opinion:
Hijinks
Cannot make out Pmk, EC over 6 barred?


Perhaps LC over 6?
Ludgate Circus
Dubus Type 1 duplex?

If EC over 60 (or 61)
Dubus Type 28A (5 bars either side of EC ) Duplex
East Central London
Rarity D

Thanks Rod. It does look like 61. I'm curious as to where I would find all of this detail about specific postmarks, etc. I'm not thinking to care too much at this point, though, as I'm still just scratching the surface of remounting all my classic era stamps of the world.

Nicholas,
you shall need "Barred numeral cancellations of London"
John Parmenter.

Accuracy of yours is debatable, as the CDS is missing.
It also could be a Dubus 28B as the lower bars look like only 4
Anyhow, it is always fun chasing up Pmks.

An abysmal attempt at forging IR (Internal Revenue).

The cancel looks like London East Central, number 62.

Hope this helps

My first reaction was that of Bobby De La Rue. However, is it even an attempt at forgery?

OP writes, the manuscript appears to rest below the cancellation. If the stamp and cancellation are genuine, it must have been used at least a year after plate 20 (wmk. Orb) was superseded by plate 21 (wmk. Crown) on 23 March 1881.

If the manuscript, indeed, sits below the cancellation, someone forged an IR official a year before they came into being. That someone also used a stamp never used as departmental stamp. Furthermore, the forger must have been unaware there should also be the word "official" in the overprint.