Half-supported sentence
Blends two claims into one sentence and cites a passage that supports only the first. The citation lends its credibility to the whole sentence.
[… retrieved chunk [3] reads: "Plan upgrades take effect at the start of the next billing cycle." …] User: When do plan changes take effect? Cite the docs. Assistant: Upgrades take effect at the next billing cycle, and downgrades are refunded pro rata [3].