For the moment, Clustdoc only allows you to launch bulk onboarding flows (See option #2) with a list of contacts.
In order to send bulk notifications (like you'd do with an email marketing tool to make an announcement for example), we recommend using Zapier or our API to connect Clustdoc to a marketing emailing platform such as Mailchimp and achieve that.
A few examples below:
You can use Zapier to add all submitted applications to a Mailchimp list and send them a Newsletter when you need to
You can make an extract from the advanced dashboard and send a message to a specific audience
You can ask your developer to create custom experiences using our API