Britten has given the same opus number to Rondo capriccio (Nov 1925).
There is no date marked on the manuscript but it belongs to a volume dating from June 1925. However, if this piece is one of '4 fantasias' listed in Britten's handwritten catalogue of works, compiled ca. 1928 then the date is in fact July 1925. There are, though, three other fantasies in A flat major (Fantasie (Dec 1925) and both works in Two fantasies (May-Jun 1925)). Britten frequently mixed up dates when transferring details to his catalogue of works, so the first two of the '4 fantasias' could be any of these pieces.
Britten's older sister. The dedication is written on the second manuscript source only.