Yes, a full enema will reach further in the colon.
It never goes beyond sigmoid, unless you turn to full left side tilt (like sleeping on left arm) after 10-15 minutes.
This is my trick, apologies if it sounds too graphic. I never warm the bottle so when I administer, the cold feeling tells me the
location of fluid and then I change the position accordingly. Usually the feeling changes within a minute but if you are rather sensitive, you can get a feel.
I do not 'feel' it every time but the 'long practice' gives me a clue nowadays.
I wonder, how suppositories will work for inflammation in colon. They are pretty much restricted in rectum (and do not act as 'local' for colonic inflammation.)