Don't get too hung up on that.
B1 level is only required at ILR application and at Citizenship application. That' 5 years down the line.
I'm sure her English would be excellent by that time after living in Uk that long.
Nobody would get deported. Those who cannot meet the ILR requirements just need to apply for another FLR until they can comply.
Good luck with the English A1 it's perfectly OK for the next 5 years.