The letter urges the Mayor of London to defer his decision on redeveloping the Earls Court Exhibition Centres, Lillie Bridge Rail Depot, and West Kensington and Gibbs Green Housing Estate until further assessments are completed. It argues that approving the plans without a full independent economic impact assessment of losing the exhibition centres, which attract millions of visitors annually and support thousands of jobs, would be premature. It also says deferring the decision until Transport for London finishes assessing alternative locations for the rail depot is prudent, as it currently employs up to 550 people manufacturing essential track components. Approving the plans before these studies are finished could compromise passenger safety and lead to additional costs and job losses.