There's a real sadness and restrained anger, perhaps, in Christine when she talks about Lindsey leaving in 87 and being replaced by Billy and Rick in the BBC documentary- just listen to the pauses...
"and we all decided we gotta replace Lindsey, and that's when we got Billy Burnette and Rick Vito and rehearsed frantically and went out on the road ...it wasn't the same .. obviously"
She was technically talking about Billy and Rick, but her body language and careful choice of words seem to indicate the 2018 sacking as well as Mike and Neil were on her mind.
https://youtu.be/FfE5fHeBWEg?t=3558