Possible Clues:

• March past, occasion for japes
• Jokester's annual fun time (3 words)
• Fair play abandoned, so old cunning accepted, at this time?
• First for fools
• Mug's date?
• Time for tricks if a lad's poorly treated
• When pranksters come out of the woodwork
• Apt time for pranksters to do the starts of 17-, 22-, 50-, and 57-Across?
• What each of this puzzle's eight longest answers is a 93-Down of
• Time for practical jokes (2 words)