SFE Application for Exchange Student

Hi,

I am currently a full-time student in my 3rd year. My university nominated me for an exchange programme abroad, which should take place in the second semester of my 4th year. However, most likely I won't receive a confirmation from the host university until October. In the meantime, I received a letter from SFE asking me to sign that there won't be any changes to my course so that they will pay me the same as in previous years. This won't be true if I'm going in exchange, but I have yet to be formally accepted for that.

What should I do? should I sign it and then ask them to change it when I get accepted? Or should I reapply now with the "change of course" form? I received the letter in March and 2 more notices since. I'd like to act now.