Shillings ceased to be used on February 15, 1971, when the UK adopted the decimal system for its currency. On that day, one shilling became worth five pence. Therefore three shillings were equivalent to 15 pence.
I doubt this ghost sign dates for the rebuilding of the pub. Indeed, once cumulative inflation is taken into account, a bottle worth 3 shillings in 1910 would cost between £13 and £14 today. That would have been quite pricey for the vast majority of people in West Ham, an industrial borough where many workers lived in slums. But maybe The Angel attracted wealthier patrons? Still I think a later date is more likely for this ghost sign.
The Angel has been empty since 2003. What will happen to it and to this ghost sign? I'm afraid they may both disappear in a near future if property developers move in.
Location: Church Street / Pictures taken on: 15/05/2011