jQuery Rails Nested Resources Bug?

Question

I have a Rails app using a form with several nested resources in it. The weird quirk about it is I am using several single select inputs as one multiple select input (i.e. Using the same name across them). I am also submitting this via JavaScript (i.e. remote: true). The select html is below:

<select name="order_item[order_item_options_attributes][1][value2][]">(...)</select>

This works fine when I am using this form for create. However, when I am trying to update, it reverts to a POST request instead of a PATCH. The _method hidden field is correctly being generated:

<input name="_method" value="patch" type="hidden">

Here is where it gets weird! If I change the name of my select inputs to order_item[order_item_options_attributes][1][value2s][] (notice the s after value2), it works!

So it seems like jQuery only allows a PATCH request if all nested array values are "pluralized". Is this working as intended or just a bug? Or am I missing something? I am using Rails 4.2.8 and jQuery-rails 4.3.1.

Edit:

Here is the relevant routes. It's just your standard nested routes:

resources :orders do
    resources :order_items
end

And the output:

order_order_items_path      GET     /orders/:order_id/order_items(.:format)     order_items#index
                            POST    /orders/:order_id/order_items(.:format)     order_items#create
new_order_order_item_path   GET     /orders/:order_id/order_items/new(.:format)     order_items#new
edit_order_order_item_path  GET     /orders/:order_id/order_items/:id/edit(.:format)    order_items#edit
order_order_item_path       GET     /orders/:order_id/order_items/:id(.:format)     order_items#show
                            PATCH   /orders/:order_id/order_items/:id(.:format)     order_items#update
                            PUT     /orders/:order_id/order_items/:id(.:format)     order_items#update
                            DELETE  /orders/:order_id/order_items/:id(.:format)     order_items#destroy

Edit 2 (Clarification):

This appears to be a jQuery issue and NOT a Rails issue. The reason I say that is I can edit the name attribute directly in the browser (i.e. Not a refresh or code change) and it will work immediately. So this seems to be something client-side and not server-side.