Occasionally, Acquia Support will send notices to Acquia-hosting customers regarding important maintenance issues. If you have not signed up for these notices, please see the Acquia Status documentation page to learn how to sign up for alerts.
In most cases, customers shouldn't have issues receiving these emails (which are sent using Marketo). If you've configured your email server to not accept certain content, you may have to add certain IP address ranges to your server's whitelist to ensure that you receive these emails.
If this is the case, add the following IP addresses from Marketo to your email server's
https://docs.marketo.com/display/public/DOCS/Configure+Protocols+for+Marketo#ConfigureProtocolsforMarketo-Step2:WhitelistMarketoIPs
If you continue to have problems receiving maintenance notices, contact Acquia Support for additional assistance.