Because the opening report is equivalent to the idea that you just started this topic (design). As you study this topic (design) more and more deeply, it is normal and permissible for this idea to change.
The opening report refers to the written explanation of the scientific research topic by the opening person. This is a new applied style with the enhancement of the planning of modern scientific research activities and the need of programmed management of scientific research topics.
The proposer gives an overview of his chosen topic to relevant experts, scholars and scientific and technical personnel (that is, "the content of the opening report"). Then they will comment on the scientific research topics. You can also use "Delphi method" to score; Then the scientific research management department comprehensively evaluates the opinions and decides whether to approve the project. The opening report is one of the basic materials for the graduation thesis defense Committee to examine students' defense qualifications.