Conditional primary receiver on PayPal adaptive payments

I'm developing a crowd funding site.

On a crowd funding page, is it possible to have conditions for the primary receiver on an adaptive payment so that once a certain target has been reached, the primary receiver is changed to a different PayPal account?

EG - if a target is £1000, anything raised upto this amount:
- 90% would go to receiver A (£900)
- 10% would go to receiver B (£100)

if target is £1000, but more (£1500) is raised:
- 90% of the target amount would go to receiver A (£900)
- 10% of total amount would go to receiver B (£150)
- Remainder would go to receiver C (£450)

Taking this further, each crowd funding project on the site would need to be able to specify receivers A and C.

Receiver A is a site member and puts the project forward. They specify a target amount of which they receive 90% of the target.

Receiver B is the site admin and always receives 10% of all funds raised.

Receiver C is specified by Receiver A and receives the surplus after Receivers A and B have had their amount.

This would all need to be possible through a front end system, rather than through the WordPress admin panel.

Please advise on how this can be done.