Made less than expected but didn't report income change to state health insurance marketplace - would have qualified for Medicaid. Should I take Premium Tax Credit?

[joviet]

I received the Premium Tax Credit for all 12 months of 2018, and now TurboTax tells me that I am entitled to an additional lump sum payment of PTC in my refund. 

I made less income than I expected to in 2018. However, I (unintentionally) neglected to change my income level on the health insurance marketplace. Had I done so, I would have been determined to be eligible for Medicaid. 

My understanding is that you cannot take the PTC if you make less than (in my state) 138% of the federal poverty line, which, in 2018, I did. 

My guess is that the software is coming up with this additional PTC because it is rectifying the difference in my expected and actual income for 2018. But, because I would have qualified for Medicaid had I updated my income, I technically should not have been eligible to receive the PTC. 

My concern is that I am not actually eligible to receive the PTC refund that TurboTax is offering me.  

[TaxGuyBill]

Yes, you qualify for the Premium Tax Credit.

There is a special rule that says if you qualify when you sign up, you continue to qualify even though your income dropped.