Update: not an awful lot I can say here, without discussing the ins and outs of what is essentially a confidential process and job. It was a hard decision; we only interviewed 2 applicants in the end but both were good for different reasons, and in the end we went with experience (JetlagGirl) over novelty (FirstEverBoy).
It was hard using my brain after such a long time off, and after having lost a large proportion of my brain during labour and the first few difficult months. But once I got back into it, it was fun, and interesting, and made me more excited about going back in (argh) just 2 months time. JetlagGirl will be starting straight after Christmas, working full time as my maternity cover until I return at the end of February, when she'll jobshare with me. She seems to be committed for the longterm which will be nice, as I don't want to have to go through all this again in a couple of months.
Day 19: Mission complete.