Can you explain what is meant by the phrase "the then existing House" as used in this article?
The phrase "the then existing House" refers to the House of the People (Lok Sabha) as it existed at a particular point in time. In this context, it means the specific arrangement and representation of territorial constituencies and seats allocated to each state based on the 1971 census. The readjustment mentioned here is likely referring to any changes or modifications made to the existing House's structure after the specified date, which would then be in effect for future elections until further readjustments are made.