Problem with rehearsal marks

[liang seng]

Hi, I have a problem while using Lilypond 2.7.17 for Windows. Here is the 
file:

\version "2.7.17"
tutti =  \mark \markup{ \small TUTTI }
\relative {

\key c \major
\once \override Score.RehearsalMark #'padding = #4

\mark \markup { Allegro } \override Score.RehearsalMark #'padding = #2.5
<< R1 { s16\tutti } >> R1 R1 R1 }

Here, I'm using the override command to prevent the Allegro rehearsal mark 
from clashing with the treble clef. I also used \once because I do  not want 
Allegro and "TUTTI" rehearsal marks to be in the same height as they could 
overlap each other (not in the example, but when there are more bars of 
music in the line, they will). I then used the override command to lengthen 
the distance of the "TUTTI" rehearsal mark from the music. I did not use 
\once as I would like all the subsequent rehearsal marks to be on the same 
height. I also used a variable to specify tutti as there are many tutti 
marks in the piece and it would be a hassle to type each one of them using 
\mark. However, as you can see, the second override command doesn't seem to 
have any effect on the position of "TUTTI". Is there an explanation to this?

mark.pdf
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