Nope, there's no "new" law regarding S-Corps.
17-AC is the gross receipts amount, to be used for 'business interest' computations on Form 6??? (?).
It appears at this stage to be a programming error.
It's not self employment income. Look at the codes for the 1120S K-1.
The input screen in Lacerte 1040 is misleading. Just don't enter it in either of the 17AC lines.
Earlier today I replied to the other post about this, but of course cannot find it now because the search function here sucks.