A 2018 distribution will be reported on a 2018 1099-R that you should receive after Jan 31, 2019. When you enter then 1099-R into TurboTax you will be asked what you did with the money - choose that it was rolled over.
The fact that it spans years is immaterial as long as it is within 60 days of the distribution.
Don't wait until the last day though, some financial institutions rules specify that the posting date (and the date they send to the IRS) can be several days after the deposit to allow for processing.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
