Paypal express - submit does not hide main form buttons when loaded as the default

Steps

1) Paypal Express is the default payment processor for a site and payment express and another payment processor are loaded on a contribution form or event.

2) On loading the page the payment express button shows but so does the form submit button. Selecting the other processor the form loads find and when reverting back to paypal the form loads find AND the submit button hides fine (desirable).

The immediate issue is that this line

https://github.com/civicrm/civicrm-core/blob/81590b0dc6065a0508076d65fc25073aba868e95/templates/CRM/Financial/Form/PaypalExpress.tpl#L49-49

Does not fire when loading the form the first time.

I'm not sure how this line should best be added / encapsulated to cause it to fire both when the form is loaded & when the snippet is loaded.