Sorry, no lefty updates at this time. Please don't give up on the Barrett team. They have a VERY full development and process engineering pipeline.
Keep in mind this rifle dropped into the market in two action sizes and about ten chamberings. That was a monumental task. Most rifle intros come in 5 or less calibers in one configuration. Chamberings or configs like stainless action, alternate stocks or left hand actions take years to roll in.