License question regarding 3.x and dynamic routing protocols

According to http://www.mikrotik.com/pricelist.php?sect=1 there are are new license limitations on dynamic routing protocols.
However, i am a little bit confused.
Does it permit running BGP on RB (MIPS/PPC) or will BGP only run on x86 hardware?

using version 3.x on RouterBOARD with license level 4 BGP is available, that limitation about bgp lvl 5 only is ONLY for x86

how about an existing 2.9 router running BGP upgraded to 3.11 ? I’ve done this and BGP works fine, but now I need to replace my CompactFlash, and purchase new (or replacement key). Does this mean a new Level4 won’t work, but my previous Level4 was still bgp capable? x86 only of course.