The Mainnet upgrade has been delayed to the week of Monday, December 9th; Hedera will provide a more approximate date and time window soon. As such, there will be no downtime nor disruption of service to either the mainnet or mainnet mirror node as previously scheduled.
Posted Dec 05, 2019 - 17:42 UTC
Hedera will be upgrading and restarting the mainnet on Thursday, December 5th at 20:00 UTC. The upgrade will take approximately 90 minutes to complete, during which time all network services on the Hedera mainnet will be offline. The update reflects the following, potentially breaking, configuration changes: Max_Contract_State_Size=1024 (should already be set), maxGasLimit=300000, maxFileSize=1024.