Furthermore, this device supports up to four OS version upgradesxii and six years of security updatesxiii, allowing for comfortable use over an extended period.
xii Up to four upgrades to the latest OS will be applied starting from the time of release. The number of upgrades may vary depending on the timing of the purchase.
xiii Security updates will be applied for up to six years from the time of release. The duration of support may vary depending on the timing of the purchase
https://www.sony.eu/presscentre/sony-introduces-its-latest-flagship-smartphone-xperia-1-vii