Remove adjacent duplicates and select corresponding values from other columns

Hallo Everyone,

I am struggling with this problem for quite sometime and can't seem to find a solution...
1) I am trying to populate values in Column D and E. Column D only keeps the first occurence of true/false and only changes if opposite occurs. e.g. if true is set, it will ignore all other true values unless a false value comes, then false will continue ignoring other falses unless true comes.

2) E has the difference between values of column A based on the values of Column D. so anytime true, changes to false and vice versa. it calculates difference between respective column A values. e.g. On row 3, true changes to false. so Column E has difference of A3-A1. Next change occurs on A11, when false changes to true. so column E has difference of A11-A3.

HTML Code: 

Any ideas / tips here ?
Thanks

Try in E4 (and copy down) the following array formula:

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...confirmed by pressing CTRL+SHIFT+ENTER to activate the array, not just ENTER. You will know the array is active when you see curly braces { } appear around your formula. If you do not CTRL+SHIFT+ENTER you will get an error or a clearly incorrect answer.