Hastings have moved back to the top after a nine-wicket win at home to Stirlands but just 15 points separate the top four clubs.
Previous leaders Horsham were beaten at Eastbourne, where former Haywards Heath player Stuart Faith took 8-41 in 14 overs, the best ever figures at the Saffrons in 38 years of league cricket.
East Grinstead moved off the bottom with a win at champions Brighton & Hove, and Preston Nomads are now second with a game in hand after their three wicket win at home to Chichester.
That memorable game at Three Bridges produced nearly 700 runs as Cuckfield won by two wickets after losing the toss and chasing leather as Michael Shaw (124), James Chadburn (79) and Danny Alderman (60) led the hosts to 345-5. Kamran Mirza took 3-49 against his former club.
But Cuckfield were up for the challenge and Tom Mole (92), Graham Beghin (79) and James Thorpe (50) sealed the win despite Paul Smith taking 4-48.
Stirlands decided to bat first at Hastings and were dismissed in the 39th over for 141 as Max Barson hit 48 and Nathan Ball 23 against an attack featuring John Morgan (3-18) and Tim van Noort (3-31).
James Beeny (77) and Toby Finzel (61no) then shared an opening stand of 132 to help their side to a nine-wicket win in only 22.1 overs.
Skipper Tom Smith led Eastbourne to victory by four wickets at home to Horsham by hitting 96 not out but hero with the ball undoubtedly was Stuart Faith with his record-breaking 8-41. Horsham were saved from total humiliation by an eighth wicket stand of 86 between Matt Simpson (41) and Alex Harding (47no) but they could not prevent their side being bowled out for 173.
It then took Eastbourne 49.5 overs to get the runs as Harding took 2-25 and Ansar Javed 2-33.
Runs were hard to come by at Preston Nomads, where the home side eventually ran out winners by three wickets against Chichester, who were dismissed for 162 as Nick Hobbs took 3-45, Kashif Ibrahim 3-65 and Stephen Rigg did the hat-trick in his 3-34.
In reply Nomads lost early wickets but 48 from Jeremy Green and 43 not out from Kashif Ibrahim enabled them to move to victory, with James McKemey helping things along with 23.
Two struggling clubs met at Brighton & Hove and it was visiting East Grinstead who won an exciting game by just seven runs.
The victors included two former Test players in their line-up and both Alan Wells and Dinesh Mongia were victims of Guy Williamson (4-13) as Grinstead crashed to 36-5. But the tail wagged with a vengeance as Stuart Simmonds hit 37 with good support came from Steve Greig and Craig Fowle to take the total to 151 all out in 51.3 overs. Patrick Spencer finished with 5-52.
Brighton were then dismissed for 144 in 57.3 overs with Chris Grammer making 38 and Luke Wells 27. Mongia bowled throughout the innings to take 5-58.
In Division 2 Bexhill have opened up a lead as nearest rivals Lewes Priory and Littlehampton were both beaten, while bottom club Sidley are still without a win after being humilated at Haywards Heath, where the hosts romped to 303-0 and then sent Sidley packing for 43.
That biggest partnership of the season was shared by Tom Dowdall (135no) and Billy Harris (142no) before Hayden James (6-11) and Joe Mennie (4-27) made short work of the reply.
There was controversy in the last ball victory by Bexhill at home to Worthing, who claimed the spirit of the game was not observed as the leaders took the second run needed for victory after the ball when returned by a fielder deflected off one of the batsmen. Feelings were running high at the close.
Dominic Clapp made 85, Andy Lutwyche 51 not out and Tim Dunn 47 as Worthing declared at 234-4, Chris Topp taking 3-59. In reply the last ball drama allowed Bexhill to get home by one wicket after Shan Adei made 71 and Chris Deeprose 46. Kyle Bowes took 5-65.
Lewes Priory were dismissed for 219 at Roffey despite 72 from Nick Seager and 70 from Ed McGregor. Luke Barnard took 5-52. Roffey then won the game at 224-7 thanks to 51 not out from Simon Shivnarain and 46 from Sam Adams. Simon Allen claimed 4-68.
Pulborough provided something of a shock with a six-wicket win at home to Littlehampton, whom they dismissed for just 104 as Matt Crump took 6-45. Chris Heberlein top scored with 40. It took the hosts 35.4 overs to seam victory.
St James's Montefiore enjoyed a comfortable seven-wicket win at Steyning after the home side declared at 181-9, of which Gary Hunt made 54. Stephen Ades took 3-25 before Saints completed the win in 36 overs thanks to teenage wicketkeeper Adam Davies making 77 not out and Ades 49.