Drinking session with bar turned upside down and filled with slime (5-2)

I believe the answer is:

booze-up

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'drinking session' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for booze-up that I've seen before include "Bout of serious drinking" , "Drinking spree" , "Heavy drinking session" .)

I've seen this clue in The Times.

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