We amended our LLC tax returns for 2011 and 2012 voluntarily.
IRS didn't issue any notice and we amended voluntarily on the basis of another CPA's review. The main issue with the original LLC return was that our original CPA deducted expenses instead of capitalizing them. The 2nd CPA wanted to be more conservative and not deduct any expenses, which we agreed. Ours is a start up (construction phase) and we haven't opened business yet.

Would IRS review/audit the original returns that were audited?
Since our LLC is based on partnership, there were no tax implications.