A knowledge base article about Can I convert my bIT managed server to self-managed or vice versa? provided by the UC Berkeley IT Service Hub - Knowledge Portal
The short answer is no. In both cases a new VPS will be provisioned as a replacement.
Servers are issued an IP address based on their operating system, SLA level (managed or self-managed), and by the type of data being stored (P1 to P4). In most cases we will need to assign your server a new IP address. The hostname and any aliases can be transferred to the server's new IP address if needed.