They don't save an ELC year. He uses up year one of his ELC this year regardless of where he plays.
I get the arguments for Lohrei to stay. I get the arguments for Lohrei to go down. Personally I believe Providence is a cesspool at the moment, and I despise the coach, and question the commitment to developing players.
Personally, i think Lohrei will learn more, and develop more quickly in Boston playing against real NHL talent, than he will in Providence. All I know is if he is in Providence, he should play the most minutes, carry the #1 PP, and play on the PK. If he is there to develop and show his skills, he darn well better be playing more than any other D, and in all situations