To make your sheet "flexible", I added some "location" columns where you can indicate where the envelopes are located. You'll see them when you open this sample sheet. If you find these helper columns unsightly, just hide those columns...but don't forget about them! This will allow you to restructure your table anytime and any way you wish and the macro will kee working.
So your Allocations sheet should now function the way you want.
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However, I've added a second sheet showing a little more standard and basic layout. It makes the update process far simpler as you can see by the difference in the macros for each of those two sheets.
So you have two working options.
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