I used to build long time ago Adaptive invul t2s pre-crius these things were in the 2.2m range and were super profitable to build right now no matter how tight you squeeze that index you're going to be building them at loss unless you're t2 bpo owner i suppose.

I hear ya mate, however you just nailed it "until people run out of the buffed BPCs", that's one of the issues, I alone have around 35000 bpcs, and one of my friends has about 98000...yea they are going to run out of bpcs when they are old enough not to be able to lift.

Perhaps you should give the market more time to adjust. Let me give you an example...

I make T2 damage controls. Prepatch, it took 1.25 hours to invent in a POS, 18+ hours to make. Based on my sleep pattern, thst 18 hours meant it was actually a day. So basically, each day I could make 100 DC 2s, limited more by invention.

Now invention was always the bottle neck time wise. So to save my sanity and avoid trips to trade hubs, I would invent in large batches. once I had enough BPCs ready, i would make them. I had a stockpike right before patch. I knew material change were coming, so the wait was planned. The patch hit... Now, instead of 100 mods a day, it takes 4 hours to make 100 mods, and well... Work and sleep hinder Eve life, but still... I can make 300 mods a day now. What would have taken me 12 days is now 4 days.

Guess what, I, like many proceed to mass produce, thinking more mods equals more money. Well... The demand didn't change, but supply sure did. I, and many others, rapidly flood the market (especially since a lot if us held off, drying up the supply, this was why t2 280mm Howie prices rose a ton prepatch). Our flood lowers the market as we compete to sell and get some if thst higher profit. However supply is huge and the market drops.

Also, my bpcs went from -4 ME to much better, meaning more profit per unit if sold at old prices or i can take less profit per and still be good. So more reason for prices to drop.

But wait... Invention times changed. What use to be once every 1.25 hours in a pos is now 4 in a station. This slows me down actually. I could get 4+ invention cycles in a day. Now I get 3 or less. So, once I burn through my existing stock, I (like many others) will actually produce at a slower rate. Prices will bounce back as the demand matches the lower supply. Also, the New bpcs have a lower ME, meaning they cost more.

So basically, you are reacting too soon. We are still in the correction phases. Give it a few months, then see what's happening.
My guess, things will balance out and the profits will be about the same.