Must be a bonus from Raintree. My 4 variety “disease resistant” apple from them had a 5th, “Summer Red” which I had never heard of.
Last year I went bonkers grafting and added a bunch of Euro pears to my Asian pear tree. Some bloom at the same time so I added them as pollenizers. All of them took, and one is about to bloom. So now my Asian pear has Orcas, Rescue, and maybe some Bartlet and others. I dont know which one is blooming. The buds are pink, while the Asian pear flowers are white.
Maybe your Anjou is there to pollenize, or maybe just because.