Hello. You need to configure every slot as a single partition if you like to achieve what you want to achieve.
make Slot 1 for Monday and direct the jobs to it. Do the same for other days. For example configure another partition with Slot 2 for Tuesday job, Etc.
But be aware that if your backup job exceeds the tape capacity in one of the partitions it waits for you to put in another tape. It will not overwrite tapes present in the same partition ( no matter how many slots a partition may contain)
Hope this helps.