Voice.autoBeamSettings fails \revert ?

[Graham Percival]

Based on my reading of automatic beam behaviour,
http://lilypond.org/doc/v1.9/Documentation/user/out-www/lilypond/Setting-automatic-beam-behavior.html
I think this example should beam sixteenths in groups of four in the
second bar, but instead LilyPond continues to beam them in three.  Did
I make a mistake, or is this a bug?

This is with 1.9.7.

----
\score{ \notes { \relative c''{
\time 12/16
\property Voice.autoBeamSettings \override #'(end * * * *) = #(ly:make-moment 3 
16)
d16 e cis d e cis d e cis \times 3/2{d e}

\time 4/4
\property Voice.autoBeamSettings \revert #'(end * * * *)
f a d, a' e a cis, a' f a d, a' e a cis, a'
}}}
----

Cheers,
- Graham