Time between 2 surveillance audits

Answer:
Yes, the standard that officially defines the maximum period between two surveillance audits is ISO 17021 (standard that defines requirements for bodies providing audit and certification of management system), and in accordance with this standard, surveillance audits shall be conducted at least once a year.

These articles can be interesting for you:

“Surveillance visits vs. certification audits” : https://advisera.com/27001academy/knowledgebase/surveillance-visits-vs-certification-audits/

“How to maintain the ISMS after the certification” : https://advisera.com/27001academy/blog/2014/07/14/how-to-maintain-the-isms-after-the-certification/

"Accreditation vs. certification vs. registration in the ISO world" : https://advisera.com/articles/accreditation-vs-certification-vs-registration-in-the-iso-world/

Finally, these materials will help you to know more about information security and the audit s in ISO 27001:
- free online training ISO 27001 Foundations Course https://advisera.com/training/iso-27001-foundations-course/
- book Secure & Simple: A Small-Business Guide to Implementing ISO 27001 On Your Own https://advisera.com/books/secure-and-simple-a-small-business-guide-to-implementing-iso-27001-on-your-own/