If a country has NDC2.0 target for reduction below the BAU for 2025 and 2030, does it need to update the BAU scenario for its BTR1 that was submitted as part of the NDC2.0 and then use it for the NDC tracking? Or it can continue using the BAU scenario that was part of the NDC2.0 submission? 

Then, if the country needs to update the BAU scenario for the BTR, is it necessary to start from the same starting year for projections in 2018 that was used for the NDC2.0 submission, or start with the latest year with available GHG data from the most recent GHG inventory that is 2023 in accordance with para 95 of decision 18/CMA.1?