Holiday Cryptic

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Across
  1. 4. Work out mode of transport (5)
  2. 6. Regularly raise arm support—it slips down easily! (8)
  3. 10. Alert satyr accidentally set off before dawn (5,5)
  4. 11. Immediately bring out our keeper—it’s in the bag! (4)
  5. 13. Use French water in recipe British author accidentally left in vile town (11)
  6. 14. This angry arrangement of letters (9)
  7. 17. Figure Steph is food for wasps! (4)
  8. 18. Essential, not to be considered “12”! (10)
  9. 20. South African lace woven for French region (6)
Down
  1. 1. Replicate a complicated painting, for example (10)
  2. 2. A bit of humour is integral in a New Testament for someone like Erasmus (8)
  3. 3. Addresses error, inexperienced driver follows foundations! (5)
  4. 5. One is English knight, “His Excellency” (self-confessed) (8)
  5. 7. South East, then left, first exit (immediately) leads you to where the library is (8)
  6. 8. Makes deliveries regularly in Alsace (5)
  7. 9. French city is calm or bonkers (6)
  8. 11. Where we changed direction initially, but Ella remembers nothing (4)
  9. 12. Sharing pickled Alsatian delight—pork, for example (7)
  10. 15. Viol signed so oddly—something like Sierra? (6)
  11. 16. Weep, spill tea on photo… Requires some thought! (7)
  12. 19. Blue trousers Steph very quietly makes for proprietor (4,4)