A: Think about it - would you mention any "emergency fallback" when presenting your grand plan?
MidLife was created as a reaction to a spur-of-the-moment Holy decision - one with the utmost of premeditated intent, certainly, yet one whose consequences were inconceivably major... major enough to call for the creation of a new realm of being.
MidLife serves as a 're-do' for lives met with irreversible roadbumps, and, ideally, should not exist at all - you should only get one chance in life, as per God's design. However, much like errors in a computer system, sometimes these roadbumps cannot be avoided... requiring a second "Earth" in which souls can finish what they started. For that reason, it's presence is ignored in all Holy writings.
Q: Does MidLife have a definite geography?
A: No. MidLife is endless - there is no here, nor there. Because of that, attempts to map our eternal cityscape have proven fruitless. MidLivvians depend on their own worldly knowledge to understand their surroundings - it'll take time, but hey... you've got plenty of it!
Q: Does MidLife have a Moon or Sun?
A: No - MidLife's skies parallel Earth's, so as to enhance the feeling of "Humanity". There are no interstellar objects beyond MidLife, as it is eternal in every plane, but there is still a visible night and day.
Much of MidLife is shrouded in a night-like darkness due to the towering heights of our countless skyscrapers and the intertwined threads of our raised highways; because of this, most citizens depend far more on the concept of time itself than on what can be visibly determined. This allows for a more more efficient and active society! Many MidLivvians come to prefer the darkness, finding it's cool, calm conditions much easier on their somewhat debilitated bodies.
However, thousands of years ago, MidLivvian engineers decided to spruce up the skyscape by inventing synthetic "Stars". These Stars are metallic orbs built using extremely thin metals, allowing the long-lasting bio-luminescent gas within to shine through the surface. These Stars brighten up both the day, and the night!
Q: I've seen MidLivvians with artifacts from their death still attached to their bodies. How is this possible?
A: What is included as part of the MidLivvian body is a question that eludes scientists and philosophers alike. The most common theory states that, if a death is caused by something external, yet something that becomes one with the Earthly body, then both are interpreted as one altogether "object".
...In other words, as Doctor Clannison would say... Hell if I know!