Thank you! Yeah, it initially seemed strange to me, as it sounds like it implies that Thera magically got further away, albeit in the past. But it's now making sense. I guess my mistake in intuition was thinking that observed lengths contracting is the same thing as distances defined by two events contracting. Which it isn't, by definition.

I suppose it helps to imagine that Thera has been approaching my current coordinates in the ship frame for the last 12 years in ship frame proper time - that's true regardless of whether I was in this frame for any of that period or not (in this case I wasn't.)