You ask a lot of questions ripandrock. Can I ask you one? Are you going to emigrate to America because a lot of your questions seem to relate to the USA? Part 61 and 141 only relate to the USA. Those rules don't apply anywhere else.
There is an Instructor forum where you can ask but basically the answer is that it depends on who they work for. Quite often an Instructor works from dawn 'til Dusk and beyond, 7 days a week when the weather is good because when the weather is bad, they sit unpaid staring at the rain and cloud. They might snatch a lunch in between lessons on busy days or have leisurely lunches when it's quiet.
On the other hand in more formalised flight schools there may a proper roster with proper days off and a salary.
As I said it depends on where and who you work for.