An expedition — a multi-part escalation chain (typically four sites) obtained by chance (~5%) from an unrated complex, tracked in The Agency. Each completed part has roughly a 50% chance to continue, usually toward lower-security space than where it began.
The Moving Day spawns in high-sec, low-sec and null-sec. How you find it: escalation only — cannot be scanned down.
What spawns in the Moving Day?
The Moving Day has 14 waves and about 91 NPCs: 26 battlecruisers, 22 cruisers, 14 destroyers and 29 frigates. Killing the trigger ship spawns the next wave; the triggers are Strain Decimator Alvi, Sentient Viral Infector Alvum, Strain Silverfish/... Alvi and Siege/Exterminator Alvatis and others.
Does the Moving Day escalate?
The Moving Day is itself an escalation from Rogue Trial Yard.
What does the Moving Day drop?
Faction/commander drops scale with the chain's depth; the fourth site carries the headline table.
Access C Single-source / unverified
Ship restrictions
Unknown
NPC roster C Single-source / unverified
Community-maintained wave list from the site's own wiki page — counts and triggers vary between spawns; treat as the shape, not gospel.