How to get a license for BIG-IP Virtual Edition Trial version 10.1.0?

Hi, I am using BIG-IP Virtual Edition Trial version 10.1.0 now, and I need a License to activite it. but I only can get a License for version 11.3.0 at https://www.f5.com/trial/secure/, and it says:"The BIG-IP LTM VE Free Trial is available as version 11.3.0 hotfix 1 for a VMware hypervisor environment." So how can I get a license for BIG-IP Virtual Edition Trial version 10.1.0? Thanks very much!