GST CROSS CHARGE/INPUT TRANSFER QUERY - Goods and Services Tax - GST

A company engaged in IT/software export services has its Head Office (HO) in Hyderabad and a Branch Office (BO) in Bangalore. Over the years, the BO has accumulated unutilized ITC of 50 lakhs (FY 2018-19 to FY 2024-25) due to a lack of taxable outward supplies. However HO is engaged in zero-rated exports and claiming ITC refunds. Considering the GST framework: Can the BO transfer its accumulated ITC to the HO through cross charge? If so, how can it be structured legally? Given the amendments effective from 01.04.2025 mandating ITC distribution only through the ISD mechanism, will the BO lose the accumulated ITC post-31.03.2025? What is the best strategy to ensure that the company does not forfeit the accumulated ITC while remaining GST-compliant?