The unboxing video
Please consider that unlocking the bootloader and installing SF could void the SONY warranty.
BUT Not everything is lost: it may still be possible to send the phone to Sony, especially in the first year. Sony in any case is capable to repair the device (reverting it to Android).
The IMEI will be the reference for the SONY for international warranty.
Jolla-Devices does not provide an additional warranty to the Sony one, the item is sold as used by Jolla-Devices.