Playing as two characters?

If I understood it correct, we chose one Ryder to play as. The other Ryder is still in the world but is not a member of the team. And as far as I know we do not switch between them.

Edit:

I actually am against being forced to play as more than 1 character.

For example, GTA V is a great game, but what REALLY frustrated me while playing it was that I HAD to play as 3 characters instead of just as
1.
This really hampered my immersion into the game and my ability to attach myself to my controlled character.

Just when I started to feel in the shoes of the character I was controlling, I was forced to complete other missions associated with another character playing as that other character.
I dunno, somehow I really didn't like it, others may love it... but I just feel plot-dizzy when I jump to other characters in plot driven games.

Well I'm not saying you'd HAVE to change character for some quests. I'm saying it would be cool if it was possible, since both characters would be voiced and are optional to begin with

Oh no
Always hated that part of DA2

Can I leave both lame siblings in cryo and play as badass N7 dad. I know I can't but I sure wish I could.

I would actually enjoy having a family member as a party member at some point in the game. Although, we all know what Bioware does to family members.....

To be fair, there is supposed to be some "learning the ropes" in the main story ark/character progression, but it could just involve the normal leveling up/learning new skills process... one of the other older, mentor like figure on the crew would still be nice, though.

I have a feeling that role has been given to PeeBee...the designated info dump companion.

This would be a very interesting start of the story narration.
I just hope Dad doesn't simply disappear at the end of the proloque via an abrupt screen fade out scene....

I worry how Bio is going to establish our family connection to be more than this is your dad/sibling therefore you care about them.  If it's just an info dump, no one's gonna care and it's gonna fail as an idea.  If the game starts with us coming out of cryo and our sibling ends up stuck in cryo, then we effectively have no connection to him/her, so why will anyone care when the inevitable "you need to save your brother/sister moment" comes our way.

Not sure that's what they meant with "hypersleep mishap"... I did sound to me like the sibling will be in the story, just in some form disabled, that could mean ie. paralyzed. So she/he could still have a supporting role (Oracle, anyone?). I doubt they would let us customize the father and the sibling only to drop them from the story completely at the start... if it really IS customization, and not the "changes along the lines of the main character" we had in DA2, of course.

Then again... it's highly unlikely that father and sibling will be "disabled", that would be really lazy writing.