The Starting Gravity That Got Away

[BasementAle]

I set out to recreate a strong ale that I brewed last year and fermented with a yeast of unknown origin. I salvaged the mystery yeast from the strong ale keg and made starters upon starters until finally getting enough viable cells to make a 2 gallon batch of pale ale. The plan was to keg the pale and pitch the strong ale onto the yeast cake. Enough of these starters. All of this went according to plan. However, having been inspired by tales of wee heavies boiled for 3 hours and really feeling the need to hit 70+ IBUs, I may have boiled off a bit more than intended. Long story longer, the Tilt at first gave me a false low SG (user error or impatience, to be sure). Regardless, there was no thought to adding back any water. Fast forward to the next morning and a correct SG of 1.147 appears. Seven days later and the gravity is plateaued at 1.111 for the last three days.

I’m questioning lots of things these days. [Removed --Mod] But mostly I’m wondering: Will the mystery yeast go the distance? If this finishes at a reasonable 1.025, will a 16% Barleywine be drinkable? What is plan B if/when the poor little yeasty warriors go down like Spartans at Thermopylae?

 

[Broken Crow]

I don't feel I have enough experience with such a brew to give a worthy suggestion other than to pitch another yeast to finish as a plan B.
I just wanted to thank you for the most creative asking of a question I've seen since @bracconiere disappeared.
As to the other:
[Removed --Mod]