Help with conditional format to highlight partial text cells

[ivpush33]

I uploaded my excel spreadsheet and lost the conditional format that worked fine on my desktop. What I have is a shift schedule, that consists of A shift , B Shift, and A/X, and finally X/B. I can only have one instance of any combination of either A or B. I want to highlight both instances of any partial duplicates per column. Example

6/1 6/2 6/3 and so on
A A X/B
B B B
X/A B A/X


Note the X is not a shift but so duplicate x's dont count, only the A or B portion. (if that makes sense)
Heres what i am using now;
=COUNTIF(B$3:$R14,B3)>1
this works fine for highlighting exact duplicates, but I need to be able to only highlight cells in a single column that contain duplicate A's or B's regardless if there accompanied by "/x" or not.

[ivpush33]

Not sure how to post this without the formatting being messed up. What I have is a spreadsheet with the employees name on the left, and the date across the top of each column. In each of the available cells is a drop down list that contains the shift that employee wants to work. (A,B,A/X,X/B) The x represents they are NOT available for the opposite shift but prefer to work the indicated shift. A/X means they want to work A shift and are NOT available to work B shift. Just a simple A means they are available to work either shift but prefer to work A. The X/B means they are NOT available to work A shift and want to work B shift.

I can only have one person per shift A or B. If one person chooses B and another choses x/B I need to highlight both fields. Or if two people enter the exact same shift , such as B, and B, then both get highlighted as well.

I hope this makes some sense.

Thanks for the help