It could have been easily written into HCR that people with existing policies would be guaranteed the option to change to any new plan offered by their insurer with a same or higher deductible to avoid blocking of business/death spirals....but that would be too easy.
Blue Cross Blue Shield of Florida has that, they just don't tell many of their subscribers about it and agents won't tell them either because there in no financial gain.
I actually tell people who are referred to me by other clients and already have Blue Cross plans about it when it makes sense (someone with a pre-existing condition or a woman who might want maternity coverage since Blue is the only one in Florida that offers a good plan)-I lower their premiums significantly by doing that and they normally add some kind of supplemental coverage or life insurance with part of the premium savings-it's a small benefit to me but I like doing the right thing. I've saved people over $5K a year a few times by doing this.