Hi Deanna
From what I can see, it's currently not possible to extend the time past 72 hours - https://help.genesys.cloud/articles/messaging-threading-timeline/.
I found the following 2 Ideas logged for similar requests, would recommend that you vote on the ideas as its currently in "future consideration" status.
https://genesyscloud.ideas.aha.io/ideas/REC-I-105
https://genesyscloud.ideas.aha.io/ideas/DIG-I-584
Regards
Stephan
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Stephan Taljaard
EMBEDIT s.r.o
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