Optional T+0 rolling settlement expands eligibility and participation, enabling parallel trading with T+1 under operational safeguards. Expansion of an optional T+0 rolling settlement permits trading alongside T+1 by widening eligible scrips to a phased top 500 market capitalisation list, allowing all brokers to participate and to levy differential brokerage within limits, and obliging Qualified Stock Brokers, custodians and Market Infrastructure Institutions to implement systems for investor participation. A morning Block Deal window for T+0 will be available, MIIs must publish operational guidelines and FAQs, and provide fortnightly reports; phased applicability and modification of prior circular provisions are specified.