Function to extract column data

Hi Babycakes 

You can refer to the following solution.

1.Create a Index column

Index = var a=ADDCOLUMNS('Table',"DayNum",SWITCH([Day],"Monday",1,"Tuesday",2,"Wednesday",3,"Thursday",4,"Friday",5,"Saturday",6,"Sunday",7))
return RANKX(FILTER(a,[Shift Start]=EARLIER('Table'[Shift Start])),[Day],,ASC)

2.Then create the following columns

Sub_Shift Start = IF([Index]=1,[Shift Start],[Sleepover Finish])

Sub_Shift Finish = IF([Index]=1,[Sleepover Start],[Shift Finish])

Output

Best Regards!

Yolo Zhu

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