I don't know if people are aware but the price of crude oil is down 50 % from its early January peak. This is a combination of a drop in demand, due to reduced economic activity caused by COVID-19, and a price war between OPEC and non-OPEC oil producers. OPEC want to limit supply through the demand turn down to stop prices falling and non-OPEC producers, especially Russia, are refusing to fall into line. This fall in crude should be reflected in a drop in heating oil prices at the pump. Obviously the drop in heating oil will not be as big, because much of the price is determined by other costs, especially various taxes, but it should be noticeable. There will be a short delay between crude and heating oil price moves but heating oil could bottom out at some time between now and the end of March. If your tank is not full it might be worth watching how the price is changing at your local supplier and top up ready for next winter.
Trying to catch the price at its lowest is a matter of judgement but it is like trying to catch a falling knife so don't worry too much about getting the timing exactly right. A saving is a saving even if, with hindsight, you might have made a bit bigger saving. Also note that, while legally heating oil can be on sale until the middle of April, many suppliers stop buying during the second half of March because they don't want to be left with unsold stock through the summer. Bad for cash flow.