Six months.
He'll only last six months at most. Mycroft's sure of it, he's done the math. He had to keep telling himself that this was the best option for Sherlock. Solitary confinement would be awful for his mental health. At the present moment, a pardon was impossible as it would only be interpreted as sentiment on Mycroft's part, and he couldn't disappear because Mycroft would inevitably get caught. Mycroft would do anything for his brother, but they had both agreed that it would do little to have them both in custody.
Sherlock was high when he got on the plain. Mycroft had seen it instantly, but he had not commented. He didn't want his last memory of his baby brother to be of them arguing. The disapproval must have been visible however, as they had a silent conversation.
What does it matter now Mycroft? My days are already numbered, why not enjoy them?
Sherlock. I didn't say a word. As you say it hardly matters anymore…
Myc, are you angry?
No Lock. A little disappointed, but not angry.
I should have told you, you're the best big brother I could ask for. I love you Myc.
If this is my best, then I'm very limited. Lock?
Yes.
I'm proud of you, for all this. For becoming a detective, for using your talents for good, and most of all, for shooting Magnussen. He was a monster, Lock, a dragon.
I'll miss you.
I'll miss you too, brother mine.
"As this is likely to be the last conversation I'll ever have with John Watson, would you mind if we took a moment?"
This is for the best.
"Yes, of coarse."
"Yes, of coarse."
As the plane took off, Mycroft could not stop thinking: Six months, Six months, Six months….
He desperately wished that he was wrong.
Then his phone started to ring…