For customers who send high email volume and want more control over their individual sender reputation, HubSpot offers a dedicated IP address for sending emails.
When you purchase the dedicated IP add-on, you can connect your new IP address in your domain settings. Once the dedicated IP is live, the new IP address is warmed up gradually to establish a healthy sending reputation.
A sudden change in sending volume can look suspicious to email filters and blocklist operators. So for the first 40 days, your email tool automatically splits email sending between your dedicated IP address and some shared IPs. The tool uses an algorithm to gradually increases sending over your dedicated IP during that time.
To protect your email sending reputation, be sure you're following all recommended deliverability best practices.