"Substantial changes" require an addendum to the contract. “Substantial changes” imply changes that affect overall the original contract and/or its annexes, on which the EDULINK Selection Committee has based its decision to award a grant. These include changes to the nature of an event, changes on systems of management, extension of the implementation duration, changes of partners, etc.

A request for an addendum should be submitted at least 30 calendar days before the addendum is intended to enter into force. This request has to be made in writing and should be well substantiated and justified. It has to be approved by the Contracting Authority and if deemed necessary, an addendum to the contract will be prepared. An addendum needs to be endorsed by the European Commission and signed by both parties signatory to the contract. After signature an addendum becomes integral part of the contract.