Was there a time gpu mining was not profitable?

If your electric was cheap enough, GPU mining was quite profitable all of last year - just not at the crazy-good levels of the last 2-3 months.
It was profitable enough I could afford to move TO the land of "Very Low Cost Electric" and go professional as a miner.

If you had an electric cost above the US average, it was barely profitable if at all (which is WHY I moved, my rates in the 3 months of "summer" were 14+ cents/kwh where I was at in Iowa, despite "Time of Day" rate savings).

I would say that last month and early this month are probably the highest-profit times for GPU mining since before the first Bitcoin ASICs arrived, somewhat more so than the peak of Litecoin profitability on a GPU - and even right now that profitability level is STILL very close to it's all-time peak.

Even if ETH and ZEC and XMR prices stagnate for the next 6 months, profitability will remain elevated due to the inability of miners to get as many GPUs as they want which will restrict network hashrate growth quite a bit and hold profitability up into the current "insanely short ROI return" levels that have spurred massive investment into GPU farms - and for at least the next couple of those months new rigs will easily pay back their investment before profitability drops enough to bring profitability back down to the "better have fairly low cost electric if you expect to pay for this investment in less than a year" range.

Unless there is a lot more price rise on the "big" coins, I still believe that the major shakeout will happen when ETH goes mostly PoS - but I figure there will start to be some low-level attrition before that given their plans to "gradually" move to PoS from PoW.

IF there IS a lot more price rise, especially if the price manages to stay ahead of network hashrate growth in the non-ETH big coins, the profitability drop when millions of ETH mining cards start looking for new homes *might* not reach the level that was seen last summer - and the growth rate will slow but not die.

I'm planning for the former scenario, but hoping for the latter.