This is a continuation of the conversation I was having with @unseen and @anonymous378 on another post. My last reply was hidden for veering off-topic so I will post it here. But first I need to explain the topic.
TL;DR:
Most people do not know nor understand that SimpleLogin and Proton Pass are separate services. Even if one depends on the other, and premium access to one grants you premium access to the other, they are still separate subscriptions and SimpleLogin is an independent product.
EXPLANATION:
If you subscribe via Proton Pass Plus, you have a Proton Pass subscription.
You do not have a SimpleLogin subscription.
Conversely, if you subscribe via SimpleLogin, you have a SimpleLogin subscription.
You do not have a Proton Pass subscription.
Even though SimpleLogin is integrated into Proton, there are ways in which it is not, like how you pay for it.
Different billing companies
As most of you probably know, SimpleLogin is not a native Proton product. It was acquired by Proton in 2022 and later integrated into its suite of services.
Despite now being part of Proton, SimpleLogin is managed by a different payment processing company. They are managed by Paddle, while native Proton products are managed by Stripe.
This is one of the reasons why the subscriptions are separate.
SimpleLogin remains an independent product
Proton Pass is powered by SimpleLogin and depends on it. But SimpleLogin is still considered a separate service because Proton wishes to maintain it as such for those who have no interest in Proton Pass.
All of this I learned from Proton Support because I wanted to seamlessly switch my payment method from Proton Pass to SimpleLogin. I assumed the subscriptions were one and the same, but they are in fact NOT. Hence, it is not possible.
Proton Pass aliases cannot be migrated (directly)
If you have two Proton Pass accounts, it is not possible to transfer your aliases from one account to the other. Almost all of your Proton Pass data can be seamlessly and directly transferred, but not your aliases.
The only workaround is to transfer your aliases via SimpleLogin, but it’s a tedious manual process. It can only be done one by one, alias by alias, and hence not in a single batch. Also, all the metadata attached to your aliases is lost during migration, meaning that Proton won’t remember which vault they belong to.