LAST CALL

For the February 10 & 11 NANOG Meeting held in San Francisco. Last day for
registration is Friday, January 31. To advoid delays at the meeting please
send in form of payment ASAP. Thanks
  Pam Ciesla

Hi,

  I want to attend this NANOG meeting but it isn't fixed
whether I can attend or not.

Now,
  1) register now and cancel if I can't attend
  2) I can register after 31th
  3) I have to register today and can't cancel if I can't attend

Which of above is correct?

Regards,