iPad Mail: Scrolling after multiple message selection

On iPad Mail application you need to dig deep into the menu to select multiple items. That would be fine to an extent, but…

When I have selected the screen length of messages to be deleted or moved, and want to add about 100 more into the same operation, the visual hops back to the beginning after every tap on a message selected, yet I’d still have multiple messages to select to the same demographic and operation of deleting them. How to just scroll down screen after screen when the next screensworth of messages have been selected?