Two rakes one saffron another regular coloured spare rake.
For example.......
Klbg smvb vb 22231 came in saffron rake on morning.
Then after reaching smvb it stayed there itself for pm @smvb due to Pitline development at klbg. So 22232 with spare rake will go to klbg and come up as 22231 the next day. After that when 22231 reaches smvb it...
more... will stay there itself for pm and then saffron rake will be sent for 22232 and it will come to smvb next morning with saffron rake. Then same thing saffron stays white leaves. Alternative rakes are used .