We've been filing the FAFSA since 2008, and I've been very attuned to the gradual changes in details. It used to be relatively easy to stay under the Auto EFC =0 limit when it was $29k or $30k or $31k AGI. Then it was retroactively changed from $32k to $23k. That was a bit harder target to reach for a family of 7, but at that point we still essentially hit zero EFC via the calculations. We did qualify for the Simplified Needs Test , with AGI <$50k, so no assets needed to be reported, but even if they did the asset protection amount was a reasonable size for our EF, maybe around $30k. Then the asset protection chart took a nose dive, too; I was shocked when it was under $6k I think. That was "adjusted", but it is still under $20k for us (as we move up the age part of the chart).
We have to file 1040 due to our HSA, but until last year we qualified for reduced lunches. We are now down to one kid at home, 2 in college, 2 out. It was the drop in family size, with a bit of income increase, that ended the reduced lunch loophole for us. The way the FAFSA rules are written, being eligible for reduced lunches in the student's senior year of HS grants 3 years of eligibility - the reduced lunch school year straddles 2 calendar years, at least one of which will cover 3 FAFSA years. So we are approaching uncharted territory (for us) when DS4 does his senior year FAFSA. He's a freshman now, and was caught in the switch to prior-prior year tax reporting, so the relevant tax years for him are 2015, 2015, 2016, 2017. Then we'll have 3 years w/ no FAFSAs, and begin again for DS5 (2021-2024 tax years). He will appear to be an only child, completely changing the calculations. I wonder how the formulas and limits will change as a few more years go by. I don't like the current trends.
I have definitely decided to forgo Roth conversion during FAFSA years - conversions increase AGI, AND Roth withdrawals are added back to income, a double whammy. I've been trying to figure out if we could get to the point of pulling the trigger on FIRE just in time to match DS5's first FAFSA, but I'm not sure, esp w/ the ACA subsidies up in the air. That one year lost to the prior-prior switch was unexpected. Another option is if DH retires but I continue in my part-time role, supplementing a bit from DH's 401k using the 55 rule. There's an awful lot of things that need to line up just right.