Standard elevation ultimately in further plan (3,6)
I believe the answer is:
red ensign
'standard' is the definition.
(I've seen this before)
'elevation ultimately in further plan' is the wordplay.
'ultimately' suggests the final letters.
'in' indicates putting letters inside.
'further plan' becomes 'redesign' (redesigning is a kind of planning. I am not sure about the 'further' bit.).
The last letter of 'elevation' is 'n'.
'n' placed inside 'redesign' is 'RED ENSIGN'.
Can you help me to learn more?
(Other definitions for red ensign that I've seen before include "standard for seamen" , "Flag for ships" , "Flag flown by the British Merchant Navy" , "Sailor's flag" , "Shipping flag" .)