So I was about to buy a course, but I have a question.

I've noticed for the lessons, some have different amounts of lessons per. I had thought the differences were only due to how many LSAT tests were explained. For example:

Main Point & Main Conclusion Questions 17 lessons, 1.6h (Starter)

Main Point & Main Conclusion Questions 19 lessons, 2.1h (Premium)

Main Point & Main Conclusion Questions 21 lessons, 2.3h (Ultimate)

I know that upgrading from one course to another gives more lessons but my questions are:

1) Will using a starter with 17 lessons versus an ultimate for 21 lessons on "Main Point & Main Conclusion Questions" be a huge difference? What are in the remaining 4 lessons?

2) If I start using the Starter and decide to upgrade to Premium later, will my 7sage program show that I have 2 extra lessons that I didn't use?

3) Are the lessons that are skipped in Starter something that might cause the following lesson to make less sense?