Wellingborough made it five wins in five outings in Group A with a 20-0 home whitewash victory against Oundle.
Neil Redding and Paul Redding (four holes), Tom Marshall and Andy Redding (five holes), Steve Coles and Ashley Connolly (five holes) and Mark Hawkins and Ciaran Eeles (six) were successful for the hosts.
Kettering have emerged as the only realistic challengers to Wellingborough after recording an excellent 12-6 success at Peterborough Milton.
Once away Club Captain Sean Suddards combined with his partner to take the opener by five holes, the result rarely looked in doubt as Kettering won three of the next four games, before Milton kept the scoreline down with a good win in the final match.
Collingtree Park suffered a first defeat in their Group B campaign as they went down 13-5 at Kingsthorpe.
The visitors looked on course for their fifth win of 2019 when they opened up a five-hole lead after just two games, but the hosts surged clear thanks to a 10-hole success for Gavin Marks and Jonathan Riddle in the penultimate tie.
Cold Ashby proved too strong from Daventry as they overcame an early deficit to stroll to a 22-3 home victory – Steven Horton and James Needham (eight holes) enjoying the biggest win.
Farthingstone leapfrogged Northampton to the top of Group C on points difference after recording 18-3 home victory against Silverstone.
Despite losing two close ties early on, Farthingstone completed the double over Silverstone this season with the help of a 10-hole win from Matthew Isaacs and Paul Dale in the closing game.
Northampton came agonisingly close to holding on to top spot going into the last round of fixtures as they lost a thrilling away contest with Northants County by the scoreline 7-5.
Hellidon Lakes proved too strong for Overstone Park in Group D as big wins from Gavin Aris and Paul David (seven holes) and Tony Inskip and Bob Thomson (seven holes) ensured they hammered their opponents 24-1 at home.