Suit warms up around summer's end (6)

I believe the answer is:

hearts

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'suit' is the definition.
(hearts is a playing card suit)

'warms up around summer's end' is the wordplay.
'warms up' becomes 'preheats' (I've seen this in another clue).
'around' means to look at the middle letters.
'summer's end' becomes 'arts' (I can't explain this - if you can you should believe this answer much more).
The centre of 'preheats' is 'he'.
'he'+'arts'='HEARTS'

Can you help me to learn more?

(Other definitions for hearts that I've seen before include "Card suit and essential organs" , "Suit in pack" , "Suit for vital organs" , "They beat" , "Playing-card suit" .)

I've seen this clue in The Telegraph.

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