3rd to 5th or 6th Gear
Block changing up gear isn't often required, but if you gain a lot of speed in a lower gear, you may find that you can miss a gear or two. As an example, you'll often need to gain a lot of speed over a short period of time on a dual carriageway or motorway slip road. This is often achieved in 3rd gear. Upon entering the main carriageway, 4th gear may be unnecessary meaning you can block change straight into 5th or 6th gear (if you have a 6th gear).