China Evergrande Group, the world’s most indebted developer, failed to deliver a "preliminary restructuring plan" it had promised by the end of July, fueling risks investors will grow more impatient just as a broader debt crisis in the nation’s property industry spreads.

The beleaguered real estate giant presented instead what it called "preliminary restructuring principles" for its offshore debt, in an exchange filing late Friday. The stakes are high, with some $20 billion in dollar bonds among total liabilities of about $300 billion. Any restructuring could be among China’s biggest ever.

Evergrande made no reference to the preliminary plan it had said as recently as June it expected to announce by the end of July. Investors had been waiting on that in hopes the proposal would provide clarity on debt extensions and asset sales. Instead they were told the developer would try to announce a specific restructuring plan within 2022.