Luke Stapleford was back on the top step of the podium in the Feature race as he beat Rhys Irwin by 1.505secs.
Ben Currie – who had been leading the points before the race - led off the line but looked to suffer a mechanical issue on the second lap when he ran off track, rejoining way down the field and spent the rest of the 14-lap race playing catch up.
With Currie out of the mix, Stapleford found himself leading and was able to slowly build a comfortable buffer as behind, Irwin and Tom Booth-Amos battled for the runner-up spot.
Irwin held off his rival to take second by 0.351secs, with fourth place going to Tom Toparis as Luke Jones was fifth.
Joe Collier doubled-up with another GP2 class win on the Kramer, just over two seconds ahead of Cameron Fraser as Harvey Claridge took third.
Quattro Group British Supersport and British GP2 Championships, Feature Race result:
1. Luke Stapleford (Profile Road & Racing Performance)
2. Rhys Irwin (Astro-JJR Suzuki) +1.505s
3. Tom Booth-Amos (Gearlink Kawasaki) +1.856s
4. Tom Toparis (Macadam Racing) +7.309s
5. Luke Jones (Highsparks Ducati) +8.194s
Championship points after Round 10:
1. Tom Booth-Amos 158
2. Luke Stapleford 156
3. Ben Currie 150
4. Rhys Irwin 145
5. Tom Toparis 127