SVN to GIT Migration update local git branches with new svn commits

I'm doing a svn to git migration using git svn. I have now done the
migration from svn to git and I have created local git branches for
each remote ref.

But my problem is if there are commits to svn to a particular branch
(eg: trunk) after the migration I thought I could use git svn fetch.
which actually works fine. but when I do that only the remote refs are
getting updated. As I said I have created local branches using,

for b in $(git for-each-ref --format='%(refname:short)' refs/remotes);
do git branch $b refs/remotes/$b && git branch -D -r $b; done

when i do the fetch my local branches aren't getting updated. Is there
a work around to do that. Also I noticed in the migration svn's trunk
is mapped to git's master branch. So my latest commits to svn trunk
arent getting mapped git's master branch when I do git svn fetch.
instead of it's updating remote ref of trunk branch in git.

https://stackoverflow.com/questions/29161646/incremental-migration-from-svn-to-git
I was following this thread which is where I learned about git svn
fetch.

Appreciate if anyone could help on this