If you are using the GO based install of Holochain, it's pretty easy to try using different versions, and updating to the latest.

In order to update to the latest version of holochain, the master branch (assuming you currently are on master branch)

cd $GOPATH/src/github.com/holochain/holochain-proto

git pull origin master

make

In order to update to the latest version of holochain, the develop branch (assuming you currently are on develop branch)

cd $GOPATH/src/github.com/holochain/holochain-proto

git pull origin develop

make

In order to try using a different branch from the remote github repo (which has name 'branch-name')

cd $GOPATH/src/github.com/holochain/holochain-proto

git fetch

git checkout branch-name

make