1st Large Diamond blue Machin definitive from retail book of 4, coded LFE
The official issue date for the Large Letter Jubilee stamps was originally 27 March 2012, the same date as the stamps for the new airmail postage rates. But the date of the increase was delayed until 25 April. However, the demand from customers to buy stamps at the old rates meant that the Counter sheet stamps were on sale in some branches early in March, the business sheets by mid-March and the booklets by 20th March, all before the originally scheduled issue date.
Even on 27th March Post Office Ltd said that this would be the nationwide issue date. Although an official instruction to withdraw the stamps was made on 29 March this had limited effect and the stamps were widely available before the date on the official Royal Mail FDCs (25 April).