Roster construction - rearranging OFF days

[darxtar]

Greetings,

This particular problem has been perplexing me for a few years now. The process I require seems such a likely candidate for automation in some way, but my knowledge gap means that it has always been a tedious manual procedure. I'm using Excel 2007.

Please consider the following cyclic roster segment:

[TABLE="class: grid, width: 800, align: center"]
<tbody>[TR]
[TD][/TD]
[TD]A[/TD]
[TD]B[/TD]
[TD]C[/TD]
[TD]D[/TD]
[TD]E[/TD]
[TD]F[/TD]
[TD]G[/TD]
[TD]H[/TD]
[TD]I[/TD]
[TD]J[/TD]
[TD]K[/TD]
[TD]L[/TD]
[TD]M[/TD]
[TD]N[/TD]
[TD]O[/TD]
[/TR]
[TR]
[TD]1[/TD]
[TD][/TD]
[TD]Sun[/TD]
[TD]Mon[/TD]
[TD]Tue[/TD]
[TD]Wed[/TD]
[TD]Thu[/TD]
[TD]Fri[/TD]
[TD]Sat[/TD]
[TD]Sun[/TD]
[TD]Mon[/TD]
[TD]Tue[/TD]
[TD]Wed[/TD]
[TD]Thu[/TD]
[TD]Fri[/TD]
[TD]Sat[/TD]
[/TR]
[TR]
[TD]2[/TD]
[TD]1[/TD]
[TD]4856[/TD]
[TD]871[/TD]
[TD]871[/TD]
[TD]871[/TD]
[TD]871[/TD]
[TD]2871[/TD]
[TD]OFF[/TD]
[TD]OFF[/TD]
[TD]871[/TD]
[TD]871[/TD]
[TD]OFF[/TD]
[TD]OFF[/TD]
[TD]2871[/TD]
[TD]3856[/TD]
[/TR]
[TR]
[TD]3[/TD]
[TD]2[/TD]
[TD]OFF[/TD]
[TD]OFF[/TD]
[TD]ADO[/TD]
[TD]872[/TD]
[TD]872[/TD]
[TD]2872[/TD]
[TD]3856[/TD]
[TD]4856[/TD]
[TD]872[/TD]
[TD]872[/TD]
[TD]871[/TD]
[TD]871[/TD]
[TD]OFF[/TD]
[TD]OFF[/TD]
[/TR]
[TR]
[TD]4[/TD]
[TD]3[/TD]
[TD]4857[/TD]
[TD]872[/TD]
[TD]872[/TD]
[TD]873[/TD]
[TD]873[/TD]
[TD]2873[/TD]
[TD]OFF[/TD]
[TD]OFF[/TD]
[TD]873[/TD]
[TD]873[/TD]
[TD]OFF[/TD]
[TD]OFF[/TD]
[TD]2872[/TD]
[TD]3857[/TD]
[/TR]
[TR]
[TD]5[/TD]
[TD]4[/TD]
[TD]4858[/TD]
[TD]873[/TD]
[TD]873[/TD]
[TD]874[/TD]
[TD]ADO[/TD]
[TD]OFF[/TD]
[TD]OFF[/TD]
[TD]OFF[/TD]
[TD]874[/TD]
[TD]874[/TD]
[TD]872[/TD]
[TD]872[/TD]
[TD]2873[/TD]
[TD]OFF[/TD]
[/TR]
[TR]
[TD]6[/TD]
[TD]5[/TD]
[TD]OFF[/TD]
[TD]OFF[/TD]
[TD]OFF[/TD]
[TD]875[/TD]
[TD]874[/TD]
[TD]2874[/TD]
[TD]3857[/TD]
[TD]4857[/TD]
[TD]875[/TD]
[TD]875[/TD]
[TD]873[/TD]
[TD]873[/TD]
[TD]2874[/TD]
[TD]OFF[/TD]
[/TR]
</tbody>[/TABLE]

Now suppose, for example, I want to move the OFF days on the 1st Monday and Tuesday of line 5 of the roster (Cells C6 and C7) to line 1 of the roster (cells C2 and D2), and ALSO adjust the shifts by moving them downwards accordingly without also moving the OFF days on roster line 3 (in other words, the contents of C5 and D5 move to C6 and D6, C4 and D4 to C5 and D5, and C2 and D2 move to C4 and D4).

Then to balance the number of OFF days in a fortnight (because Roster line 1 now has 6 OFF days while Line 5 has 2), a similar operation is performed to move the 2nd Wednesday and Thursday (cells L2 and M2) on roster line 1 to roster line 5 (cells L6 to M6), again adjusting the shifts accordingly upwards to accommodate where the OFF days will be moved to, but preserving the OFF days on roster line 3 (L4 and M4) to keep them where they are.

Is this at all possible to achieve, either as a VBA routine or otherwise? A solution would be greatly appreciated, and put an end to this tormenting problem.