The DTRF2020 Updates: DTRF2020-u2023 and DTRF2020-u2024, and Preparation of the Third Update

DTRF2020, the latest realization of the ITRS calculated by DGFI-TUM, has been updated with two new solutions, DTRF2020-u2023 and DTRF2020-u2024. They contain additional observation data of the four contributing techniques, VLBI SLR, GNSS and DORIS, from three and four years, respectively.We present the results of these two DTRF updates and discuss the challenges associated with performing annual updates in comparison with calculating new DTRF solutions every five to six years.In early 2026, the ITRS Center requested new contributions from the IAG Technique Services for the third update, covering data up to the end of 2025. Where new time series are already available, we present initial analysis results, focusing in particular on the datum parameters.