The most common and most likely answer to this crossword clue is the 7 plus 3 letter word CHANNEL HOP
I've seen this crossword clue in Independent
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Buddy explains!
The straight part
We know that "move from 4 to 5" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case move from 4 to 5 = channel hop.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 CHANNEL HOP mean?
CHANNEL HOP verb- To quickly scan the channels on a television using a remote control.
- The act of changing the channel on a television
- The act of a programme changing from one channel to another