What’s “policy quarantine” in some regional ISPs?

What it is:

• Mail held in limbo rather than delivered or bounced
• May be reviewed by postmaster or automatically processed later
• Neither immediate delivery nor clear rejection

Why ISPs use it:

• Uncertainty about sender legitimacy
• Allows manual review of suspicious patterns
• Reduces risk of blocking legitimate mail

Symptoms:

• No bounce, but no delivery
• Mail appears lost
• Delayed delivery (hours or days later)

Regional variations:

• Some regional ISPs have unique quarantine policies
• Less standardized than major providers
• May require direct contact to resolve
• Cargo held in customs inspection. Not cleared, not rejected, just waiting.