This is a different issue from:
In that case a series of failed payments leads to a single payment which is a multiple of the original amount.
In this case two subscriptions are being created for one account. It happens in the ballpark of 1% of the time. Since only one subscription can be tied to a user, the other subscription is orphaned, and just charges the user with no impact on s2member.
In at least one or two cases, the second subscription was charged against a credit card that was used in a purchase from weeks ago.
This is on version 191022
Has anyone else experienced this?