SP4: HTML Container Cache: Drop down menu are not flushed on parent nav bar when modifyng ACL

I have a Section1 with some subpages (section1a; section1b; etc..). With one users belonging to a "Managers" group (RWA from home page), I put all my pages in the HTML cache (including the home).

Then I removed ACL for guest and Maangers on one of my section1a in my left menu (from section1).

When goiing in live mode on the home page and accessing to the drop-down menu, I could still see the Section1a page in my drop down menu. When going on Section1, my left menu is correct.