Re-opening a decision that was already made, with the original board, the original reasoning, and whatever has changed since. A reconvene is not a fresh session: it chains to the prior decision, so the advisors argue against their own earlier positions rather than starting cold, and the record shows how the call evolved.
Reconvening is the practical answer to the fact that strategic decisions are rarely one-shot — the premise moves, a number lands differently than forecast, a constraint disappears. Decisions that are revisited on evidence outperform decisions defended on commitment.