This fare has been around for a while, last I’d seen this was in November.
not many destinations on the west coast. SJC is one for €1.455.
Booked ams-lhr -bos-clt-ric/ ric-jfk-lhr-ams and upgraded lhr-bos to F using avios.
there was a schedule change for lhr-bos and I was able to change the return to jfk-lhr-ams because jfk is just less then 300 miles from ric.