No truth.

VBD's bid among themselves, monthly. This takes place before schedules are bid for. Once the VBD bid is complete, you are effectively based in which ever base you are awarded. Now fast forward to the monthly schedule bid. The VBD guys bid according to their overall system seniority in whichever base they are awarded. For example, if the most senior pilot in the company, was VBD, he would bid #1 in whichever base he was awarded, each month. Now to work back to the question...line holders get 12 min days, reserves get 12 days except for 3 months, in which they are reduced to 10. This is published beforehand, annually. The chances of being VBD, ending up as a reserve, in a base with only 10 days off, every month of the year, is very small.