Bradley Perie was back on the top step of the podium after beating Lee Johnston to the Feature race win by just over half a second.
The Appleyard Macadam rider took his second victory of the weekend as recently re-crowned champion Jack Kennedy took third in what is set to be his final Supersport race before he moves up to Superbikes.
Jamie Perrin ended the race in fourth place, just 0.184secs behind Kennedy as Jamie van Sikkelerus rounded out the top five.
Jack Scott was back in control of the GP2 action as he took the class win from 11th place, just ahead of Jake Archer as Harvey Claridge finished third.
Quattro Group British Supersport Championship & British GP2 Cup, Oulton Park, Race Two:
1. Bradley Perie (Appleyard Macadam Racing)
2. Lee Johnston (Ashcourt Racing) +0.504s
3. Jack Kennedy (Mar-Train Racing) +1.024s
4. Jamie Perrin (Jamie Perrin AP) +1.208s
5. Jamie van Sikkelerus (MPM Routz Racing) +8.822s
Championship positions after Round 18:
1. Jack Kennedy 401
2. Bradley Perie 284
3. Harry Truelove 232
4. Lee Johnston 192
5. Luke Stapleford 185