Portfolio: how to have several stories in progress for one team member?

[Vincent Teyssier]

Hi,

In portfolio, I have team members with let's say 8Hrs capacity per day.

I assign 2 user stories to team member X.

Story 1: 16Hrs. Start date: 01/07/2017
Story 2: 24Hrs. Start date: 01/07/2017

Doing like that I will have the stories one after another according to backlog priorities.

But what I would like to do is to have my team member work 4 hours per day on project A and 4 hours per day on project B so both user stories run in parallel for the same team member.

Another example would be to assign a routine task to a team member, let's say 1 hour per day, and he would work on other stories the remaining 7 hours.

How can this be done in portfolio ?