Chelsea U18 defeated Arsenal 3-1 on Saturday.
Second-half goals from Isaac Christie-Davies, Harvey St Clair and Cole Dasilva gave Chelsea a15th league win of the campaign.
The youngsters will now take part in an eight-team elite playoff round, playing the top four from the north section and the other top three from the south either home or away to determine the national champions.
Joe Edwards made four changes from the side that beat Fulham 1-0 last weekend, with Jared Thompson, Richard Nartey, Cole Dasilva and Jacob Maddox returning to the team.