An OAuth token represents a relationship between the application and the user account. As a result, only one token per user account is granted. In fact, if you try to authorize the same user multiple times for your application, the Twitter API will give you the same token back each time.
You should definitely move away from managing all your advertisers under a single user account. That’s a bit of a doomed strategy in terms of product growth. This approach will be extremely limiting and you’ll constantly be fighting with all kinds of rate limits (not just on stats).
The best option will be to create and manage many user accounts, one for each advertiser, on behalf of your customers and authorize your application under each of those accounts.
This can be a bit more difficult to manage, but it’s the best option if you’re in a situation where your advertisers are only willing to give you promoted-only access and don’t want to grant your application a user token for their own account.
I highly recommend taking a read through our guide on obtaining ads account access. This guide outlines both recommended strategies for account authorization depending on the level of access you require.
It’s worth noting however that while we allow you plenty of flexibility in how you choose to manage user accounts, you won’t be allowed to create multiple user accounts for a single advertiser as a means of circumventing rate limits.