Hi @edwardr28531298
Yes, it is possible to have a new blacklist in 9 Hours but there could be a couple of things to be mindful of here:
1. Are you applying all the suppression rules you have in your typology to your workflow while running the counts? In case workflow does not have all the suppression as the typology has, it could give you extra suppression while the typology is being applied during actual send out.
2. Its always good to have a recalculation of suppression rules during the send out.through typology. Of course, that would mean different counts during running the initial counts and the actual send out counts.
3. Also, check the blacklist check applied through the typology and in the workflow to make sure they use the same exclusion logic to get more accurate counts.
Not sure if I understand your situation exactly but these points could come in handy while running counts.
Thanks,
Anup