If you have the funds to invest now, you can contribute $5,500 to a tIRA now for 2016 and then another $5,500 after January 1st as your 2017 contribution. Sounds like you are just starting out so make sure you have a decent emergency fund on hand before you prioritize saving .12% on fund expenses.
Ah, and one thing that I always did if I knew the tIRA was going to make sense was to contribute as early as possible. In other words, you'd have from 1/1/17 to 4/15/18 to make your 2017 contribution. Over many years, getting that money in 15 months earlier adds up (never did the math but it has to be a considerable amount over time).
Good luck!