As you probably already know, a key aspect of the vCampus membership is the personal development PI System you can get from the vCampus Download Center, which is set to expire at the same time as your membership. Since that date is part of the PI Server License file you used to activate your PI Server, an essential step for you to extend the lifetime of your development system is to re-generate that PI Server License file (such that the new expiration date gets taken into account).
As explained at the top of the vCampus Download Center, you can do that from the My License Activations (MLA) section of the Technical Support website. The best way to get there is to use the "Link to MLA" hyperlink in the top-right corner of the vCampus Download Center. This links contains your personal vCampus system's unique identifier and will present you with a view of MLA that only contains that server - not all your other (e.g. production) PI Servers.
Note that PI Server License files are machine-specific and therefore you will be requested to upload a Machine Signature File (MSF) - you can generate this file using the MSF Generator, found on the vCampus Download Center.
Once you have your new PI Server License file (a file called PILicense.dat), simply copy it to the \PI\dat directory of your personal PI System (and override the existing one). The PI License Manager checks for license changes every 10 minutes and will automatically detect the new file.
Hope this helps! Please don't hesitate to reply to this post or write to us at vCampus@osisoft.com if you need further assistance.