Calculating End Date

[lukerumbelow]

Hi,

I've searched and searched and so far haven't found a solution to my issue as most are trying to use the FORECAST or WORKDAY inputs and these either won't work or aren't required for what I'm trying to do.

I need some help calculating a forecast end date based off a start date and % completion. I've spent hours going back and forth and just cannot crack it and I'm pretty sure that I'm very close, I just can't see the wood for the trees.

I've attached two images of what I've got one of how it shows and one with formulas. I am trying to calculate the bottom box based off the % completion, so it would show if a project was due to finish early or late etc? What am I doing wrong and what formulae would get me to where I want to be? (ps.. Yes columns B&C are merged... I took them from another document which required this for formatting)

Thanks!

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