Time is never a good metric for anything in my opinion. Here is what you must to do before starting link building.
1) Completing all To-Do for your site
2) Creating 5-10 Pillar contents
3) Choosing magical topics which can drive highest traffic and have low competition. Now make the highest quality content possibile on those topics.
4) Do On-Page and Technical SEO
Now if you are satisfied.
Start building Backlinks