how to SVN regenerate [ man awk ]

For $giggles$ I svn up /usr/src/usr.bin/awk  or wherever, then
man awk displays not the newer import per a recent SVN but
the older 2015 [ it says ] one.  Stale file, or not all parts of
the man page updated to include latest revision dat, or some
other command to [g]unzip or whatever, besides 320.whatis
in periodic--weekly, update the compressed latest installed
files from /usr/obj to what one expects when one has just
recompiled the  man page?

This crops up quite a lot on this machine, so I am unschooled in
some principle of updating this operating system.  

If it matters, I receive a 

WARNING manpath environment variable set

when starting an additional
xterm & ...