Midwives are always there to assist for both pte and sub. Senior midwives may also help deliver for sub. But sewing is done by docs. A different doc may be checking you every few hours, depending on the time of the day (they’re rostered to take charge of the delivery ward), but led by a more senior doctor. I was a pte patient but always went into labour in the middle of the night, so the on call team took care of me, and then they changed shifts in the morning and in the afternoon. My gynae would check on me when she reached work for the morning, and was also there for the delivery and sewing. Honestly, I think it was fine to be checked by other doctors in between, because they were all very professional about it.
Mid wife will be there to assist for sub. And yes, if you have a long labour, different doctors will checked in with you. I personally preferred one gynae hence I chose pte