A manual layer selection by the user persists through switching masters for the tab. Unless you switch masters with the respective glyph open for editing, then the glyph will go along and switch to the master layer.
It is not a good idea to have the software make a guess to which other layer the user may or may not have wanted, and thus override a clear user choice with a guess.
Better: you can switch to the next layer with View > Navigation > Next/Previous Layer. (Good idea to set other keyboard shortcuts though, because the Opt-Shift-Up/Down will not work in edit mode.) So, switch master with Cmd-1,2,3…, then your shortcut for Next Layer should bring you to your Bracket Layer right away, assuming it is the first special layer on that master.
Or, separate the alternate design in a separate glyph with a dot suffix. Makes it also easier to keep the oversight in Font view.
That sounds like a bug. Will investigate and file an issue.