I know colleges look at your senior year grades for grade drops, but do they look at the rigor of your classes and new gpa and possibly rescind you if you are applying Early Decision or Early Action??
The rigor of your classes senior year and the grades you get are of secondary importance to what you have already done. What a college that you get into ED or EA won’t like is if you drop two or three classes after you have already been admitted ED or EA.
Or RD.
Any change in coursework that is different from your application needs to be reported to the college.
Any acceptance letter will have Terms & Conditions spelled out. Often, a grade below a C risks the admission being withdrawn.