My Mystic Meg take on it is that Bath have been pressing him for a decision and he then decided to stay with us, but then Bath increased their offer which is now making him think ££££££'s again - hence the interminable delay.
Saints are not happy in having him to the end of the season disrupting the team and not getting anything for their investment and would like to go now if he is going so they can restructure the team before the season really gets underway, but Bath are happy to wait and don't want to pay a fee when they can get him for £0 later this year.
You read it here first (all this pure guesswork that is).