The most common and most likely answer to this crossword clue is the 4 plus 3 plus 4 plus 2 letter word FROM THE WORD GO
I've seen this crossword clue in The Times
F
R
O
M
T
H
E
W
O
R
D
G
O
Buddy explains!
The straight part
We know that "as soon as possible" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case as soon as possible = from the word go.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.