In aviation we all have our own technical definitions for words.
Careful there, not appropriate to have your own definitions when there are correct ones ..................
From the Concise Oxford:-
limit
n. & v.
-n.1. a point, line, or level beyond which something does not or may not extend or pass.
2. the boundary of an area.
3. the greatest or smallest amount permissible or possible (upper limit; lower limit) (my bolding)
So, in this context if it does not or may not extend or pass beyond a point, line or level, it stands to reason that it is at that point, line or level at its greatest. It then follows that it is inclusive and, in this debate, results in an upper limit consequently being part of the restricted airspace.
Since when did Aviation regulations have to comply with usual english grammar
I'd suggest, forever.