Hey, sorry for the delayed response.
To answer your question, yes you are in the tie breaker round though no its not limited to just one letter, you can use any letters. It's basically just the same thing as last time except you're not limited to one letter and you can use any letters you want.

"The contest only requires one paragraph, of four sentences.
The length of the sentence is up to the writer."

Hopefully that clears it up? If you're still confused or have questions lemme know and I'll try to explain it better.