None of the "contracts" appear to have gone further than a UKdepot, followed a few years later by sale into the surplus market. The contracts list merely appears to have been an early sales projection by the Ministry of Supply (as was), and "gaps" or other discrepancies may have no significance at all. The only numbers with some sort of history appear to be the PF 4xx,xxx series, which appear to have been created by the sale of un-numbered action bodies to the UK gun trade.