The most common and most likely answer to this crossword clue is the 6 plus 8 letter word SECOND THOUGHTS
I've seen this crossword clue in The Daily Telegraph
S
E
C
O
N
D
T
H
O
U
G
H
T
S
More clues leading to the result SECOND THOUGHTS
- Anxiety about minute details?
- However, the conclusion of Brexit is in more doubt
- Doubts, however, beginning in third, harboured by those in boxer’s corner
- After little time, however, good person reverses change of heart
- A rethink in support — nevertheless stumped up
- Revised opinion, albeit ahead of time, penned by assistants
- Support ideas causing change of heart
- Doubts are back, ideas follow
- Doubts, even if temporary initially, harboured by assistants
Buddy explains!
The straight part
We know that "change of heart" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case change of heart = second thoughts.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.