From the Glasgow Website
The other big news for Championship sides is the lowering of the points limit for team-building to 40. Each side must again have a British rider on a three-point average at No 7 – but riders who have previously raced in the second tier, but not achieved the three-point average, can come in on a minimum of two points.
Seems pretty clear to me - With "Previously raced" and "Not achieved the three point average" being the important parts,
So my understanding of the above is all riders start off on a 3.00 unless they have a GS average having ridden enough matches and any not achieving 3.00 start on the average they have achieved but go no lower than 2.00.