I know it seems like a lot of difference, but I would go with the later date. If you have a history of going over 40 weeks the later date will give you some breathing space before they begin threatening induction and you don't want your little one undercooked before they force her to evacuate

I am sure this is very stressful for you, but I am sure bub will come when she is ready regardless of EDD (I hate EDDs btw, I think they cause unnecessary pressure on mum and bub).

(((hugs)))
Tanya