RSPBA has updated the requirements for the G1 MSR for the 2023 season. 

"...for the 2023 season there is a requirement for the Grade 1 bands to submit 1 x MSR of a Maximum 4 Parted tunes (where the tune was written as a 4 parted tune) and 1 x MSR of a Minimum 4 Parted tunes (the current format)”."

See here for more info: RSBPA G1 MSR