The surname is mostly recorded as ALPEROVITCH.
ALPEROVITCH, JOSEPH
Mother's maiden surname: MILCHENSON     
GRO Reference: 1906  D Quarter in WHITECHAPEL  Volume 01C  Page 269 
His father was most likely Davis ALPEROVITCH.
Marriages Dec 1899 
ALPEROVITCH, Davis        
MILTSENSOHN,    Rachel
Mile End    1c   981
Naturalisation record on Ancestry states that his father is a Tailor 
known as A. DAVIS, born c1877 in Russia, the son of Joseph and Annie.
Joseph with his family in 1911.
https://www.familysearch.org/search/ark:/61903/1:1:XWPW-8M1Cross checking with the 1921 census, the 'A' is for Alfred.
Debra  
