Something bothers me about the age of Kasumi. Given the timeline, they awaken ten years after embarking on the trip to Elysium. Kasumi awakens at her 18th Bday. That would mean she went in at 8 years old. But Umiko says she was a bratty teen. That doesn't add up. So I believe Kasumi is 28 instead of 18.
Wildman Dev would you weigh in on this to clarify?
There are two ways you can count time when you talk about cryo—the method you're using would invalidate everyone's age, though it is applicable.
The way I chose to do it is that when you go into cryo, your age and years stop because your body stops decaying. So, if you went into cryo at age 39 for ten years, you'd still be 39 when you woke up ten years later.
I'm equating the aging of a person's body to the age that they say they are. It both makes sense and kinda doesn't, but the way we count time and years is very human and Earth-constructed, so in general, it's a weird subject.
If you've seen Interstellar (I don't want to spoil this for you if you haven't) -
there's a scene where time passes quite differently for two sets of characters. This example isn't really related to cryo; just that it shows how a person's aging can be separated from "time."