Any subscription still in a trialing status does not count towards your Monthly Recurring Revenue (MRR), as the subscription is not active and there is no predictable revenue for that subscriber.

If a subscription transitions from trialing to active, the subscription will then count towards your MRR even if the first invoice is unpaid. Eventually, if the subscription is cancelled or marked unpaid due to the unpaid invoice, the subscription will no longer count towards your MRR and will count towards your churn.