After I rotate an eccentric BB backwards (counterclockwise, when facing it from the drive side) for chain mounting purposes, once the chain is installed and once I get proper chain tension (from rotating the BB clockwise), where should the crank spindle be relative to the seat tube?

In other words, should the crank spindle be visually as close to centered with the seat tube? By the looks of it, depending on chain tension, it could go up to a cm forward or backwards from center of seat tube, which might affect my fore-aft positioning a bit. That distance from center may be noticeable or negligible, I don't know (yet) until I ride it.

Any tips would be appreciated. Thanks.