Visual mode: Inconsistent behavior with built-in text object selection

Describe the bug
When in Visual mode, doing ap or aw consecutively will highlight more and more; the current selection doesn't get reset.

This stands in contrast with how my af keybinding for "around function" is currently behaving; if I move and use it a second time to try to include another function, it instead resets the selection to only the new function.

Perhaps I've misconfigured something somehow?

If this is somehow expected behavior, is there a workaround?
My usecase is deleting two functions right next to each other, so I can move them somewhere else in one paste, instead of moving them one after the other, or relying on register shenanigans.

Output of :checkhealth nvim-treesitter

Output of nvim --version

NVIM v0.12.5
Build type: RelWithDebInfo
LuaJIT 2.1.1787165859
Run "nvim -V1 -v" for more info

Additional context
Config:

vim.pack.add { 'https://github.com/nvim-treesitter/nvim-treesitter-textobjects' }
require('nvim-treesitter-textobjects').setup {
  select = {
    -- Automatically jump forward to textobj, similar to targets.vim
    lookahead = true,
    -- You can choose the select mode (default is charwise 'v')
    --
    -- Can also be a function which gets passed a table with the keys
    -- * query_string: eg '@function.inner'
    -- * method: eg 'v' or 'o'
    -- and should return the mode ('v', 'V', or '<c-v>') or a table
    -- mapping query_strings to modes.
    selection_modes = {
      --['@parameter.outer'] = 'v', -- charwise
      --['@function.outer'] = 'V', -- linewise
      -- ['@class.outer'] = '<c-v>', -- blockwise
    },
    -- If you set this to `true` (default is `false`) then any textobject is
    -- extended to include preceding or succeeding whitespace. Succeeding
    -- whitespace has priority in order to act similarly to eg the built-in
    -- `ap`.
    --
    -- Can also be a function which gets passed a table with the keys
    -- * query_string: eg '@function.inner'
    -- * selection_mode: eg 'v'
    -- and should return true of false
    include_surrounding_whitespace = false,
  },
}

-- You can use the capture groups defined in `textobjects.scm`
vim.keymap.set(
  { 'x', 'o' },
  'af',
  function() require('nvim-treesitter-textobjects.select').select_textobject('@function.outer', 'textobjects') end,
  { desc = 'Around [F]unction' }
)
-- other irrelevant keymaps

Start with the configured select.select_textobject entry point and the af mapping shown in the issue, then reproduce consecutive ap/aw selections in Visual mode and compare them with af. Done means the selection behavior is consistent or the expected workaround is documented, with a regression test covering repeated text-object selection.