Klaviyo: Email Marketing & SMS

I think it's very shady that Klaviyo instantly charges more for additional email recipients beyond your plan level, but that when you clean your list, the plan cost stays at the higher level - unless you dig into the settings and change it back down.
A message should come up when 'Active' users drops below your biling level to ask if you want to lower your plan level. It's clearly to maximise revenue - but in an underhand way.