How to dynamicaly update sales reps

Is there any way I can tie a customer record with a sales team in such a way that when I change the reps in the sales team, the reps on existing customer records automatically change? I'd prefer not to have to run mass updates whenever I change the sales team.

I've done the following:
[LIST]
[*]Created a sales team
[*]Created a sales rule
[*]Set up a sales territory
[/LIST]

So...when we create a new customer record, the customer gets assigned to a sales territory. This, in turn, assigns the customer to a sales team.

I anticipate adding more members to the sales team. Whenever I add a new rep to the sales team, any existing customers associated with the sales team do not update their sales reps. In other words, it seems that when I assign customers to a sales team, the customer record gets associated with the sales reps who were on the team when I created the customer record, not with the sales team itself. Does that make sense?