4 10 Acre flights sounds about right. You will want a good amount of overlap between the sections. Try for at least 3-4 passes/images worth.
If it were me I would use the linear flight planning tool and use 6 passes with the along track overlap set to 80% and the across track overlap set to 83%.
This will give you 6 looks at everything along the path of travel and 4-6 across track which should have good results.
You should take off from the spot between sections 1 and 2 and at the spot between 3 and 4 to minimize travel/setup time and time between visits to the areas. This leaves the overlap between segment 2 and 3 being the one with the most time between visits so you should use some extra overlap there.
I would recommend processing each section individually using the downscale by 1/4 option in Step 2 just to verify that it will all work.
