Alternate positions are not numbered. Each member has an objective score that can be calculated at any time (see Understanding the Slotting Process).
The objective score is used by the computer during initial slotting for most activities.
Currently the computer does not slot or notify:
Hawk Mountain Activities
Summer activities managed by wings or regions
Activity directors manage their alternate lists according to the needs of their activity based on when a slot opens up so it is not possible for us to esitmate in what order or on what schedule a slot might become available for the activity you are interested in.
For example: Blue Beret has an exact number of beds and a limited number of female beds so the first alternate selected might not be the person with the highest objective score depending on the gender of the bed assignment that needs to be filled.
Other activities may wish to replace a slot from the same region or wing, if one is available, etc.