Dyson says this will last 10 years without filter maintenance. Well, if you are like me at home, that would be true since I can fill up my Windtunnel air once a month.
At work, though, during winter months, that will mean 12 times a month. Meaning I'll clog up the post filters within 2 years or less (which as you noticed were made extra large for this vacuum to be "lifetime").
Really I can't see this ever being solved. If the cyclones work as they have to, they take air from the sides, then spin around, then the dirt falls in. The air doesn't flow out of the cyclone on the bottom, but gets sucked from the top. I'm sure if I took one apart it might not work like other cyclones but they can't feed air through the bottom of the cyclones since that defeats the filtering.
To expand that new flexible tip at the bottom of the cyclone would require air flowing through it. Where that air goes depends on whether or not it can filter properly. Maybe it feeds it out back to the main chamber. Othewise, Dyson is tied to the same laws of physics as everyone else.