"Harlan Grove" wrote...
....
=REPLACE(A1,1,COUNTIF(A1,"*/*")*FIND("/",A1&"/"),"")

to return A1.
....

Might as well avoid a function call.

=REPLACE(A1&"/"&A1,1,FIND("/",A1&"/"),"")

not that the first concatenation is instantaneous. This would be a minor
time-storage trade-off.