Sequential Recipient

Hi!
Let′s say I have 3 operators on the site… and a supervisor.
To make thing even, I would like to split the ammount of emails that each operator gets.

So, when a user submits a form, I has to be sended to: operator1@mail.com and supervisor@mail.com

When the next user submits a form, I has to go to: operator2@mail.com and supervisor@mail.com

Next inquire goes to: operator3@mail.com and supervisor@mail.com

Then it starts over to: operator1@mail.com and supervisor@mail.com

I have read in the docs about Selectable Recipient with Pipes.
And saw a few answers about sequential numbers to track the amount of submits.
I think that two things together can solve my problem

Can anyone help me with that?