Greetings!
The premium do it yourself version of turbotax online should be able to handle K-3's with no issues. There are generally plenty of people who have K-1's with box 16 checked for K-3 and file them without K-3's and then amend to include the K-3 at a later date when they are released. It's a common strategy. Please see below for features for each product of Turbotax:
https://turbotax.intuit.com/personal-taxes/online/file-your-own-taxes/
https://turbotax.intuit.com/personal-taxes/online/
Best regards!
