Been on reserve forever!!! I had this same thing come up and I DID go to contract admin AND our legal dept. The final determination was that if you are on first fly AND have the lowest leveling you can be assigned a STBY. If you are on first fly and have higher leveling than a guy no on first fly, he will get the STBY and you will be assigned a flying TRIP if available. You can check with contract admin and legal but I expect this is what you will be told.