Assumption: Single-pass atomic delivery

Three raw width-two packets arrive once, in order. A supplier may buffer, but may not measure, demultiplex, select, or decode them. Every arrival occupies its full width atomically.

All laboratory quantum data, work, records, and output count toward $Q_{\mathrm{peak}}$. Classical storage is unrestricted. There is no uncounted storage, auxiliary shared entanglement, return of intermediate quantum data, or quantum export before all horizon packets have been consumed.