Unfortunately, TurboTax is extremely unlikely to fix it. This calculation has been around for 11 years and they have never expressed any interest in changing it and have even vehemently claimed there is no problem.
Unless it converges to under $1 change, it doesn't fit the criteria for the Iterative calculation and it would use the alternative calculation. And although 400% is the most common problem, in certain scenarios 100%, 200% or 300% can also cause problems.
If you have a spreadsheet, then as I suggested before, just unlink the 1095-A from the business and enter the health insurance cost where K-1 asks for non-Marketplace insurance. That should result in the proper numbers.
