Brendon Louw and Stuart Thompson scored unbeaten half centuries in wins for Ballyspallen and Eglinton, while Bilal Iqbal made 88 as Donemana beat Glendermott on DLS.
Holders Brigade were stunned at Beechgrove as Louw's unbeaten 67 from 55 balls (7 fours, 1 six) saw Spallen chase down 159.
Graham Kennedy also hit 7 fours and a six in his 40 from 28 balls, while elder brother Stephen applied the coup de grace with a breezy cameo of 20 as the win was secured from the penultimate ball.
Earlier there was no indication it would be anything but a resounding win for Brigade as Ifty Hussain (62) and Andy Britton (52) got them off to a flier before the innings lost momentum and they tailed off making 158 for 7.
Stuart Thompson 69 not out helped Eglinton to an 8-wicket win over 2017 champions Bready.
Chasing 142, the Irish international struck 5 fours and 3 sixes in his 55-ball knock, sharing a second wicket stand of 104 with Tommy Orr, who impressed with 42 from just 29 deliveries.
Earlier Mike Erlank (2-19) and Andy Millar had taken two wickets each as Eglinton kept Bready to 141 for 6.
Ross Dougherty (48*), David Rankin (31) and David Scanlon (21*) all among the runs.
Donemana ran out 23 runs winners (DLS) at Glendermott.
Bilal Iqbal hit 88 and Dwayne McGerrigle 45 as they ran up 180 for 3.
David Cooke (26) and Keshan Wijerathne (25) helped Glendermott to 106 for 6 - two wickets for Gary McClintock when rain stopped play.
The weather meant the two Championship matches went to bowl-outs.
The Bee Gees are the Germans of the NW, claiming their second victory of the month in the shoot-out scenario, while Ardmore got the better of Killyclooney in their contest.