Compare the supplied or authorized primary sources against a dated baseline. Return meaningful before/after changes with URLs and observation dates, separate event dates, unchanged pages, and failed checks. Label business implications as hypotheses. Do not infer deletion from unavailable pages. Propose a monitoring schedule only if the tool supports persistence and scheduling.

MY MATERIAL AND CONSTRAINTS
Fictional baseline: Acme plan page September 1 lists 5 projects for $20/month. Current supplied snapshot September 9 lists 8 projects for $20/month. Release blog is inaccessible.