Sorry belay the last entry,late at night looking
at the wrong clue! Wrong day for washing down
with booze (4) ?INE I can only think of WINE
unless anybody knows better.
J
That's a pity; SIND is incorrect and does not conform (much) to the clue's logic.
SIN=wrong; OK - D=day; OK, but "washing down with booze"? The criteria for proof in this last component are not satisfied, therefore the posited light is unsound. Sorry.