When you work in a higher grade on a particular day (eg. if you are an MF-licensed CSA and do a stint in the ticket office), you should be paid at the rate for the higher grade. Even if you work in the higher grade for only part of the shift, you should be paid at the higher rate for the whole shift.

It has come to our attention that management seem to be in the habit of paying Higher Grade Working (HGW) rate for only that part of the shift actually worked in the higher grade. RMT has written to them pointing out the agreement that LUL reached with the unions in 2000 to pay the higher rate for the full shift.