J-1 Waiver questions, Urgent help need ! THX

Hi everyone,

I am working at NIH. I need to get my Waiver done soon.
One thing is clear now is that I have to leave my current lab.
However, I did not receive any offer now. To save time, I would like to
initiate my waiver paper work. I have start the the first step.I received
the J-1 waiver application form. Since I did not have any offer yet. How can
proceed the Waiver? To apply for a case number, one has to write a
statement of reason. Can I write a general reasons? Or I must to
wait for the offer letter? Many THX.