Random Numbers

I have the following spreadsheet that generates random times within a specific time period and random numbers from 1 - 11. What I want to have is a non repeating random number between 1 and 11 to fill the 4 time periods. Not sure if this can be done and still maintain the row spacing? Also is there a way to have C and D 6 and 7 and C and D 9 and 10 automatically sorted when recalculated? Thanks for any help.