the suggestion seems to be the correct way to upgrade package in packrat lib.
Know also that
packrat::packrat_lib() contains the path to the packrat private library. It can be useful.
If it is working for you, can you mark your question as solved
If your question has been answered don't forget to mark the solution
Folks in the future can come along and easily see what worked for you.
You acknowledge the person who solved the issue.
If you're the original poster and the category allows solutions to be marked there should be a little box at the bottom of replies that you can click to select that response as your "solution."
Based on replies by
It will help other knows the status of the question right from the list of question or by searching for related topic.
I edited your post to add a more readable formatting