General outline history
As per Statham.
Registered - 16 September 1852
PTP - 30 November 1852
EKU - 1 January 1853
Taken from press May 1853?
Repaired May/June 1853?
173-7 registered 20 July 1853
PTP November 1853?
EKU State 2 - 9 February 1854
Taken from press April 1854?
Repair completed 27 April 1854 (engraving book)
PTP late May 1854?
EKU State 3 - 1 July 1854
Defaced 24 August 1854
Later states study
Images used are ascribed to their owners by full name apart from Bill Barrell [BB], Graham Wylde [GW], Winston Hollins [WH], David Lewthwaite [DL], Kevin Maunder [KM] and Scott Treacey [ST].
Key stamps
155 PK p 21Apr1854 [WH] This stamp is in state 3 and is dated early for a perforated stamp.
Position IL has two dateable stamps in state 2.
AP 2018-19
* I've found that certain areas of the plate had another repair between the accepted first repair and the second repair. This seems to involve the retouching of some of the weakest check letters without any re-entry (as far as I can see).
One of the things I've noticed is that many of the letterings from the last repair have strong curving lines in the lower right corner of the background. [WH]