The most common and most likely answer to this crossword clue is the 10 letter word POSTDATING
I've seen this crossword clue in Independent
P
O
S
T
D
A
T
I
N
G
Buddy explains!

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.
What does POSTDATING mean?
POSTDATING verb- To occur after an event or time; to exist later on in time
- To assign an effective date to a document or action later than the actual date
- To affix a date to after the event.
- A later citation of a lexical item.