I only tried the SOS button once, but canceled the countdown
Don't think there any forms for my country, as BMW Assist isn't available here.
Also, I think the account got activated, because at one point I tried Teleservices, just to see what happens and it went through gathering data-sending data-data successfully sent. I also have an "your hotline number" in the Connected Drive section.
Germany offers 3 years of this service included. But it's also a matter of 'my country doesn't have BMW Assist, but the service got activated over there and it should be still valid'.