Use the formula below:
=NoFilter(If([Day]<>"Fr";[Value];[Value]+If(RelativeValue([Day];([Date];[Day]);1)="Sa";1;0)*RelativeValue([Value];([Date];[Day]);1)+If(RelativeValue([Day];([Date];[Day]);2)="Su";1;0)*RelativeValue([Value];([Date];[Day]);2)))
Then add one block level filter as : [Day] Not in list ("Sa";"Su")