2623: Half-day closing?

29 29-36’s 14 13 31 25 1D 2 24, in which 1 Down and 24 are each non-words that concatenate two real terms. Unchecked, unclued letters spell out SEXY DUTCH X-MAG.

        Across

   1    Fling marauder off base, across main road (7,6)

   9    Husband going inside can slim (4)

11    Distinguished mayor’s robing on the way to work (10)

12    Semi-smooth iron instrument (4)

16    Keen on crossing river passage before others (5)

17    Cycling team’s muscles (5)

20    Coach, theirs regularly taking shower (7)

21    WW2 commando’s language in court (7)

23    Scrooge perhaps first on since November (7)

27    Diffusion of oxygen, sulphur and iodine in spongy...