vs19/vs20 no longer A350??

Checked my reservation for August and noticed it's no longer an A350, both lhr/sfo sfo/lhr are 789, and, of course, seats selections got mangled.
Daily 18:00 San Francisco (SFO) I 12:15 Heathrow, London (LHR) 3
VS 20 Non-stop Boeing 787-9 (789) 10:15 Effective 2020-03-28 through 2020-05-14
The flight arrives 1 day after departure.
Daily 18:00 San Francisco (SFO) I 12:15 Heathrow, London (LHR) 3
VS 20 Non-stop Airbus A350-1000 (351) 10:15 Effective 2020-05-15 through 2020-10-23
The flight arrives 1 day after departure.