I too found the F1 HY18 report difficult to understand....

I too found the F1 HY18 report difficult to understand. Interestingly Investor Presentation snapshot of the balance sheet highlights : 1.5x net debt/EBITDA operating well within covenants. When covenants are at the forefront of the presentation management and servicing of borrowings are playing a large part.

The article that peterapo posted on 8 August is well worth another read. This is an extract on the level of indebtedness:

"Limiting your downside risk is an important part of investing, and financial health is a key determinant on whether ARQ is a risky investment or not. Alarm bells rang in my head when I saw ARQ’s high level of debt at 0.41x equity, and its low level of cash generated from its core operating activities, covering a mere 17.89% of debt. Furthermore, its debt-to-equity ratio has also been increasing from 35.34% five years ago. Although, EBIT is able to amply cover interest payment, cash management is still not optimal and could still be improved. Or the very least, reduce debt to a more prudent level if cash generated from operating activities is insufficient to cushion for potential future headwinds. The current state of ARQ’s financial health lowers my conviction around the sustainability of the business going forward. ARQ has poor near-term liquidity, with short term assets (cash and other liquid assets) unable to cover its upcoming liabilities in the next year, let alone longer term liabilities."

Perhaps the market has concerns on company's ability to service its borrowings given the levels of EBITDA now being reported?