Some Surface Laptop 4 customers may report double the disk size in the Storage Sense UI (Start – Settings – Storage) than what is available or installed on the device. The disk size is correctly reported in File Manager and the Disk Management UI. For example, a device with 256GB will report as 512GB in this Storage UI only.
This unintended change is only in the text description. There has been no change to the actual storage size equipped in the devices sold. This issue is resolved in the latest Windows update (1904x.1151 or later). Check Windows update to get the latest changes.