Chelmsford won 2-0 on Canvey Island, despite the hosts having the better of the first half.
But less than 60 seconds into the second half it was the Clarets who the lead when Scott Davies was allowed too much time and he drilled beyond keeper Louis Wells.
And Chelmsford wrapped up the win with 12 minutes remaining when a cross was played into the box, with Lee Barnard claiming the last touch.
Relegated Braintree Town became the first side to lower the Saints colours this season as they won 1-0 at Cressing Road.
Marc-Anthony Okoye`s first goal for the Iron after 64 minutes eventually proved enough to make it a decent Bank Holiday weekend for the Iron after they drew at Whitehawk on Saturday.
That means East Thurrock United are the only unbeaten team left in the division.
The Rocks won 1-0 at Princes Park against a Dartford side for whom this was also a first loss.
Lewis Smith scored the only goal of the game after 20 minutes.
Newly-promoted Havant & Waterlooville won the battle of the Hawks to leave Whitehawk rooted to the foot of the table and still looking for a first victory.
Lee Bradbury`s side hammered the Sussex Hawks 4-0 at Westleigh Park.
Jason Prior bagged a first half brace, with Alfie Rutherford and George Barker also finding the target.
Truro City`s third win from seven came at the expense of a now second-from-bottom Weston-super-Mare side at Treyew Road.
Tyler Harvey gave the White Tigers a 33rd minute lead.
Cody Cooke eventually doubled that with 64 minutes gone on the clock.
Jake Lee reduced the deficit 11 minutes from time, but the hosts held firm.
Hemel Hempstead Town were minutes away from bouncing back from Saturday’s 3-0 defeat at home to Dartford with a win at Grosvenor Vale against Wealdstone in front of a crowd of 966.
It was a tight derby affair all through but sub Callum Driver was the man who broke the deadlock, bundling home a corner after 72 minutes later to give Hemel the lead.
But the hosts drew level with 2 minutes of stoppage time left when a cross was converted by Dan Fitchett at the far post.
Bath City, 1-0 winners at home to Poole Town 48 hours earlier, went down to a 2-1 defeat to Gloucester City at Evesham.
Bath began the match well, only for the hosts to take a 24th minute lead through Joe Parker.
Zack Kotwica doubled that advantage 9 minutes into the second half.
Jack Compton pulled one back with a free-kick, but it came with only 3 minutes remaining.
Hampton & Richmond Borough came back from Saturday`s home defeat to Havant to win 1-0 at Park View Road against Welling United.
The Wings now find themselves fourth-bottom after being unable to cancel out Ryan Moss` early 5th minute opener for the Beavers.
Bognor Regis Town`s second defeat came at Nyewood Lane against an Eastbourne Borough side for whom this was a second win.
It also took just one goal to secure the points as recent signing from Worthing, Kane Wills, popped up with the 72nd minute winner.
Newly-promoted Chippenham Town`s second win came at the expense of Oxford City at Hardenhuish Park.
Some indifferent defending saw City fall to a 7th minute Will Richards goal, but battled back almost immediately through Zac McEachran.
But goals from James Guthrie after 17 minutes and then Andy Sandell 10 minutes into the second half, saw the Bluebirds into a 3-1 lead.
Matt Patterson replied from, the spot on 65 minutes, but City weren`t able to find a leveller.
Hungerford Town earned their first win since the departure of manager Bobby Wilkinson.
The Crusaders won 2-1 at Tatnam against Poole Town, for whom this was a second Bank Holiday defeat.
Luke Hopper gave the visitors a 15th minute lead that Will Spetch cancelled out 6 minutes into the second half.
But Louis Soares` 63rd minute second for Hungerford proved to be the winner.