From version history of Dorico 6.1:
Select More.* When using Edit Select More starting from a single selected system or
frame break, Dorico will now select only breaks of the same type.
Moreover, the first ‘Select More’ (Ctrl+Shift+A) for system breaks should only select all system breaks on the current page. Only in the next step are all system breaks in the flow selected. This corresponds to the behaviour of ‘Select More’ for other elements and it would be helpful to rearrange breaks just on a single page.
For other items, Select More expands the scope first to the bar, then the system, then the flow. (The page/frame doesn’t come into play.)
In the case of system breaks, there’s only ever one per bar and per system, so it makes sense that it selects all within the flow.
If you want to manage breaks on a single page, it’s pretty easy to select the first one, then Ctrl/Cmd+click the last one, then do Select More to select all the ones in between. (This works with other object types as well.)
Select More starting from a single selected system or
