I don't know that there is a limit. However, if you have a great number of 1099s, I'd recommend using the Desktop platform of TurboTax (CD/download). The online platform may give you a little trouble when filing an inordinate number of 1099s. Here's a link to the Desktop editions of TurboTax.
https://turbotax.intuit.com/personal-taxes/cd-download/
*** I am NOT a tax expert. I am a seasoned TurboTax user, and volunteer to provide assistance to TT users. Nothing I post is to be considered TAX ADVICE; I bear no legal liability for responses.***
