After the redevelopment plan and accompanying documents have been submitted by the agency to the legislative body and at any time prior to the adoption of the plan, the legislative body upon the recommendation of the agency, without additional agency public hearings, may change such plan, or change the boundaries of the project area to exclude land from the project area, after receipt of a report and recommendation from the planning commission concerning such changes. The planning commission may recommend for or against the changes. Within 30 days after a change is submitted to it for consideration the planning commission shall make and file its report and recommendation with the legislative body. If the planning commission does not report upon the change within 30 days after its submission by the legislative body, the planning commission shall be deemed to have waived its report and recommendation concerning the change and the legislative body may proceed to act upon the plan without the report and recommendation of the planning commission. The legislative body shall consider any proposed changes at a public hearing reopened for that limited purpose.