Limit to number of in-channel products?

I saw a related post from 2014, but wanted to check if anyone is aware of a limit to the number of in-channel products?

I already have about 100, but need to add about 200 more.

Also, is there any other way to submit in-channel product information other than the developer dashboard? I'm really not looking forward to using that clunky interface to add 200 product codes...