The certificate you receive will have a 36 month (3 year) expiration, we are not allowed to issue a new certificate after the 3 years until the reassessment has been performed and any non-conformances closed off.  We therefore put your first surveillance visit after 9-10 months instead of 12 to give you some protection, your next surveillance will be 12 months after the 1st.
When we re-issue your certificate you do not lose any time as the dates will continue so you do not lose money and we are not stealing time from you.  The gap is there to protect your certificate continuation in the event of non-conformances being raised during your reassessment, sufficient time is included for you to close those issues off.