What are the criteria for obtaining an AS number?
RFC 1930 states: "An AS is only needed when you have a routing policy which is different from that of your border gateway peers".
This means that you will be connecting to two or more Autonomous Systems with different routing policies.
In your request you must show us details of the routing policy you will have when you multi-home in the very near future.
The template(s) you need to complete are found in the "RIPE NCC Autonomous System Number Request Form", which is located at:
More information can be found in the RIPE Document, "Autonomous System (AS) Number Assignment Policies and Procedures".