The most common and most likely answer to this crossword clue is the 4 plus 6 letter word POST OFFICE
I've seen this crossword clue in The Guardian
P
O
S
T
O
F
F
I
C
E
More clues leading to the result POST OFFICE
Buddy explains!
The straight part
We know that "Before, it was on every 24" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case before, it was on every 24 = post office.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.