SK 945 ARN-ORD on Friday Jan 25, 2019: success from Plus to Business with 25500 points.
Originally in Go but rebooked two days before flight to Plus for whole trip (HEL-ARN-ORD-RDU/RDU-IAD-CPH-HEL) for 762 euros and then submitting upgrade request with very low bid maybe 50 hours before departure and it did not long to get confirmation.