Cryptic crossword No 3,911

Across

1. Showbiz hub in second-class thoroughfare (8)
2. Holiday allows threesome! (8)
3. Go on the booze, to pee endlessly (4)
4. Furious about uprising, powerless, yet spurred on (10)
5. Progressive's smears suppressing Republican article (8)
6. Blunder by key worker (4)
7. Fat, degenerate and German! (6)
8. Dry, needing fresh air before beginning to drink (4)
9. Propose a little giftshop in Exeter? (5)
10. And the others? - late getting back (2,2)
11. Dress men delivered (5)
12. Being unable to get off, I struggle with onanism (8)
13. Calling for change to holiday, Oscar comes in for 1st of April (8)
14. Dusky maiden, Ms Davis, for example, about to flee (8)
15. Prepare for alien to find Earth? (6)
16. Honed clues afresh, in a timely manner (2,8)

Down

1. Beat delinquent brother without hesitation (5)
2. Court where old man gets tense before 10 (5)
3. United will expect defeat kicking-off (3)
4. A hack, perhaps, frames unknown European follower (7)
5. Secretive to a degree, I support City (6)
6. Decent condition of open prison (4,4)
7. Bond film? (9)
8. Agree with lecturer, on reflection (3)
9. Greek god has everyone crossing river coming to nought (6)
10. Record in field event after American disqualified (4)
11. Failed to have distributed (4,3)
12. Grab that woman's posterior (6)
13. Become ill, taken aback in foliage (3)
14. Privately, Victor loses his head (5)
15. See 6d
16. Recorded, as score might be (5)
17. Wife, Australian, providing child (4)
18. The French camp, yet to be revealed (6)
19. Writer's co-op cuts a dash (3)
20. Vagrant Baz can harangue online (9)