Class 153 + 170 on Snow Hill Line today

[12CSVT]

153364 + 170635 were seen working the 1317 Worcester Shrub Hill to Dorridge and 1446 Dorridge to Worcester Shrub Hill today.
Is this the booked traction for these workings ? I thought all LM passenger workings on this line were booked 172s.

 

[northernrailer]

Yes this is the booked traction for this service, im sure this is something to do with retaining traction knowledge.

 

[Old Hill Bank]

The formation then works 1617 Shrub Hill to Dorridge and 1803 back to Stourbridge.

The other non 172 job is the 0735 Shrub Hill to Dorridge and then back to Snow Hill which is booked 2 x 170/6.