Hi Yara,
To accomplish this, you could use Audience Segments to create one segment per cohort (e.g., Corhort A, Cohort B), ideally as dynamic segments based on each persons registered/attended sesssions, and use those segments to target cohort-specific push notifications and/or emails so each group only received messages tied to their particular schedule. For overall accouncements, simply send notifications without any segment filter (or to an "All Attendees" segment), so everyone continues to receive general communications regardless of cohort or session. Hope that this helps!
Thanks,
Julianna Hampshire
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Julianna Hampshire
Lead Customer Success Advisor
SalesforceGenericAccountUnited States
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