To be exact 37301 and 37302 has been in service for 4 days and the other 37303/4/5 have been in service for just under 2 weeks

You are correct about 35191/2/3/4 have transferred to Slatyford. 35190/5 still remain at Shields with 35190 being on the 17/18 boards today with 35195 unknown today.
the next round 37306/7/8/9 should be entering service in the next few days. This will replace the 2 Darts ad the first 3 MANviros, im going to guess that its 39704/10 and 39708 that go first as there in the worst condition.