As an aside issue, crews used to draw up the route on a 1:3M chart and draw in early warning lines, SAM MEZ etc. They would generally use a common standard such as red for SAM and Blue for Early Warning. SAM site positions and other markings could be displayed in varying styles.
Around 1967 Group issued guidance on colours and styles etc but this still took a long time for the Plotter to draw up the detail. Sqn Ldr George Gayton (later Wg Cdr OC 85 Sqn), Ops 1 at HQ 1 Gp acquired a Mason Dyeline Printer (sic) and created a master chart so that the intelligence base was produced to a common standard and positions double checked. Before that it would have been possible that mis-plotting occurred between different target folders. This saved a lot of time.