Automatically add value to column B when a value is added to column A by an outside source. separate sheets

[renraw9002]

I have two separate sheets in the same file. The main sheet A, the main sheet most users will actually interact with, and a hidden sheet B that gets values automatically added to it by a couple of different outside sources. My problem is originally I was using xlookup to have column A of main sheet A look at column B for the date, then it would go to hidden sheet B and look at the date in column B there then pull the number from A when a value was added to column A on secret sheet B. However the date on column B of Hidden B is also auto-populated by an outside source, but due to the way these other systems work I won't be able to have the date of column B on Hidden B get populated until 2 days after the number on Hidden B column A is already there. So the value I need from Hidden B column A is just sitting there when I need it on main sheet A column A the day before the date on Hidden B column B gets populated. Clear as mud? great. Sadly I don't have microsoft excel on my home computer. I tried my best to figure out how to use xl2bb without it, but I am not a clever man. Here's a couple photos to hopefully help somewhat.

 

[AlphaFrog]

Alternatively, you could have a formula mirror column A on the hidden sheet assuming the dates on both sheets always align in the same rows as in your images.

=IF(ISBLANK(SecretSheet!A2), "",SecretSheet!A2)

 

[renraw9002]

Alternatively, you could have a formula mirror column A on the hidden sheet assuming the dates on both sheets always align in the same rows as in your images.

=IF(ISBLANK(SecretSheet!A2), "",SecretSheet!A2)

Unfortunately they do not. That was just me trying my best to provide something resembling an example. Due to the outside sources as well there is the rare occasion where column A hidden B gets populated, but the date on hidden B won't. Idk why. When this happens the material numbers just end up at the bottom of column A hidden B in a jumble, but when the date gets populated 2 days later it corrects itself on the hidden sheet.