@SubNo: you are correct, or close. (1067)
https://en.wikipedia.org/wiki/Group_R
R2B 1390cc to 1600cc Naturally aspirated Petrol 1030 kg Two-wheel drive 2500 per year Ford Fiesta 1.6 R2[9] 927cc to 1067cc Turbocharged Ford Fiesta Ecoboost R2 R2C 1600cc to 2000cc Naturally aspirated Petrol 1080 kg Two-wheel drive 2500 per year none 1067cc to 1333cc Turbocharged none RC5 R1A Up to 1390cc Naturally aspirated Petrol 980 kg Two-wheel drive 2500 per year Toyota TMG Yaris R1A[2] Up to 927cc Turbocharged none R1B 1390cc to 1600cc Naturally aspirated Petrol 1030 kg Two-wheel drive 2500 per year Renault Twingo RS R1 927cc to 1067cc Turbocharged none
And it is also opened for similar engine in R1. So we could potentially see a R1 Fiesta with detuned R2 engine.