As from April 7, 2022, Sentinel-6 Michael Freilich is becoming the altimetry reference mission. This means that it is taking over the homogeneous precise altimetry record, a critical role for global mean sea level measurement. Sentinel-6 Michael Freilich is the fifth reference mission, taking over Jason-3, Jason-2, Jason-1 and Topex/Poseidon. Afterwards, this role will be handed over to Sentinel-6B after its own calibration phase (launch is planned for November 2025).

Both redundant altimeters onboard Sentinel-6 Michael Freilich have been calibrated over their predecessor on Jason-3, as well as all the components of the altimetric system, including the precise orbit determination instruments (GNSS receivers, LRA, Doris), and the radiometer. Sentinel-6 Michael Freilich had been following Jason-3 30 second behind, ensuring the features measured by both were the same. 

On April 7, Jason-3 will be shifted on a new, interleaved, orbit, much as Jason-1 & 2 had been. Starting April 25, 2022, this will provide denser coverage for mesoscale applications.