Answer: First it is important to note that ISO 27017 and ISO 27018 are not certifiable standards (some certification bodies "certify" against ISO 27017 and ISO 27018, but only during an ISO 27001 certification process, because ISO 27001 is the only certifiable standard in the ISO 27000 series).
Considering that, the ISO 27001 certification is valid for three years.
2 . Are there surveillance audits every year as with ISO 27001?
Answer: If your certification body includes in the certification an statement that you are also compliant with ISO 27017 and ISO 27018, the surveillance audits will be the same as for a normal ISO 27001 certification, normally one each year.