When I choose "adjust from here" on my reading plan it does not change on the iPad.
If I 'mark read" on the iPad then a new plan is created. If I then delete the plan on my Mac and create a new one, it does not get to the iPad, even if i do nothing on the iPad side and wait for 24 hours.
Then again, as soon as I do anything on the iPad, yet another plan is created.
Changes on the iPad do reflect on the Mac, just not the other way around.