There is some confusion when it comes to BTC Market or USDT Market and sometimes it is difficult to decide to take profit in which currency, BTC or USDT.

I give you an example here and hope anyone can explain in detail.

ETH was 0.035 BTC few months ago and it was around 400$ USD. I did not took the profit and did not sell Eth.

Today, ETH is 0.028 BTC but in USD it is around 540$. (buz BTC price is high)

Now if i had sold it earlier at 0.035 BTC, so today's its worth would have been 660$.

So what's is the best approach in this case to get the maximum profit ?