R Build Timeout During Package Install?


I am trying to figure out how to get our R package to build on travis. It includes a large number of packages to install, which is currently hitting the time limit. My understanding is that these will be cached, but only after at least one successful build. Our current travis config is pretty basic (https://github.com/bimberlabinternal/OOSAP/blob/Dev/.travis.yml)

I came across one old post on this issues, in which another user reported a similar problem, and their build timeout limit was increased (https://github.com/travis-ci/travis-ci/issues/7173).

I came across the idea of multiple build steps and warming the cache (https://docs.travis-ci.com/user/build-stages/warm-cache/ and https://medium.com/ubc-launch-pad-software-engineering-blog/optimizing-travis-ci-pipelines-36973aea3758). This seems like a good idea, but unless I misunderstand it, I would still need to get my dependencies to install once without timeout. This seems like perhaps it could be valuable, since if our tests fail, this would not blow our package cache though?

Is there a current best practice solution for building an R package with a lot of dependencies on travisci? Thanks for any help.