Lyric discussion by lourology 

Cover art for A.M. lyrics by One Direction

it's about the band itself, their friendship.

they're reminiscing on the great times they've had together, having a good drink and a good laugh and wanting to pause this moment of the bliss of being surrounded by loving friends.

i read somewhere that it's the "aftermath of their careers" or just before they depart for break. they want to break clocks and forget about time because they're feeling a sense of not wanting to leave what they've achieved and the memories they've shared behind.