Hello, we are a 501(c)(6) trade org that files 990 and 990-T.  On Sch C of 990, we report our lobbying totals and compare to what was on our dues notices for the year.

If you underestimated on your dues notices, you can pay a proxy tax, or add the additional lobby $$ to the next year's estimate of lobbying totals.  We chose to add the additional lobby costs to our 2024 lobby totals, but the 990-T is still computing the proxy tax due for 2023, with no way to override it to Zero it out.

Anyone else have this issue, and how did you resolve?