My own recollection of what distributors do to fill orders is to ship clearly marked parts that are of a more costly but otherwise satisfactory grade, either for performance, temperature range, or packaging, in order to fill an order.

Since manufacturers packaged and labelled other manufacturers' dice back in the day ... it's much less common now ... it's conceivable that they might have packaged 150 ns parts in 200 ns-labelled packaging.

What Erik's pointed out is, of course, also plausible, though I'd wonder why the expense of relabelling is necessary to fill the order.

RE