I have just been in a dialogue with stripe support over another issue where I wanted to change the api ID.

Stripe has changed their module, so it is no longer possible for us to change the api ID manually to e.g. premium-1-month.

Here is the message it got from stripe support:

I got your message about setting custom price_id, I'll do my best to help :
You should be able to set a different price_id by clicking on the '...' icon on the right of the price, then 'Edit price'. The following panel should contain the 'price_id' field, which could be under 'more options' :
For more context , the ability to set custom price_ids is something that was only available during one update. Stripe accounts created during this time have the feature, however it was deleted from following updates, so Stripe accounts no longer support this.
This is why you might no longer have the option to modify your price_ids, even with the aforementioned method.
If this option is no longer available to you, and it is important for your business to be able to set custom price_ids, I can send a request to our developers to enable it.
I hope this helps. If you have any further queries, don't hesitate to get back to me.
Best,
Lucas