Loop last measure of a Loop

Let's say I have a 16 beat loop set, is there an easy way to jump to a loop that loops the last four beats of the loop?

If for instance I shorten the auto loop beats to 8, 4, etc. it loops the beginning (left side of the loop) Is there a way to switch this to loop the right side - last 4 beats?

16 beat:

abcd efgh ijkl mnop

8 beat:

abcd efgh

4 beat:

abcd

What I want is an easy way to loop instantly: mnop