Laravel/PHP flatten multidimensional array

I’m wondering if someone can help with the following please? Currently I have this array:

    array:1 [
      "blocks" => array:3 [
        0 => array:1 [
          "component" => "TextColumns"
        ]
        1 => array:2 [
          0 => array:1 [
            "component" => "TextColumns"
          ]
          1 => array:1 [
            "component" => "TextColumns"
          ]
        ]
        2 => array:1 [
          "component" => "TextColumns"
        ]
      ]
    ]

What I want to achieve is a final array of the below:

    array:1 [
      "blocks" => array:3 [
        0 => array:1 [
          "component" => "TextColumns"
        ]
        1 => array:1 [
          "component" => "TextColumns"
        ]
        2 => array:1 [
          "component" => "TextColumns"
        ]
        3 => array:1 [
          "component" => "TextColumns"
        ]
      ]
    ]

If I use array_flatten or laravels ->flatten() I do not get the desired results as it flattens it too much:

    array:1 [
      "blocks" => array:3 [
        0 => array:1 [
          "component" => "TextColumns"
        ]
        1 => array:2 [
          0 => "TextColumns"
          1 => "TextColumns"
        ]
        2 => array:1 [
          "component" => "TextColumns"
        ]
      ]
    ]

Any help would be appreciated!

Thanks