Markup for end of Mark / John 8?

Question

I can't see anything in the USFM docs that looks appropriate to mark up of the 'longer ending' of Mark, or equally the woman caught in adultery in John8.  In different references in Paratext, I see a lot of different approaches, from some dashes in a \pc to square brackets and so on, but our committee haven't decided how, if at all, they want it marked yet (ignoring them or putting them in a footnote is certainly going to cause problems with acceptability).
I'm currently guessing that a ranged-milestone is a good solution, which can then turn into whatever is decided on, but is there a 'best practice' / suggested marker for this?

If not, then I'm kicking the ball into motion, suggesting a ranged-milestone for "problematic source text" (\zpst-s\* to \zpst-e\*).