Change cell value depending on date

Need a little help and this time I think it is possible I just lack the computer know how to pull it off.

I have attached a summary spreadsheet so I can reference as I go but I will give a little back story first. I want to create a spreadsheet that I can view and at a glance see who is traveling on a partcicular date and when they are due back. The problem is that the personnel will travel several times a year and I don't want to just create a giant spreadsheet with loads of dates.

Cell A3 is just the persons name and serves as no consequence for what I am asking.

In cell B3 and C3 I want to be able to display when the person is NEXT traveling and when that person is NEXT due back. Now this is the tricky part, I want this to automatically change the value of the cells after the date has passed.

In E and F I have put example dates. So lets say the 10th of July passes I would like the Outbound to change to 20th of Aug, and so forth. The same would apply for the inbound.

My thoughts were I could just dump all the dates at the bottom of the spreadsheet off the page break and have the text white so it is not visable and the sheet will be neat and tidy. There will be several people to track and I dont like clutter. :D

If anyone is particularly clever, could I even host all the dates for cells B3 and C3 on sheet 2 of the spreadsheet??

Once again, any help would be greatly appreciated.

Thanks & Regards
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