First it's merely a promise to not prosecute companies for offering soon to be illegal insurance. That provides no protection from civil liabilities, the insurance polices will still be illegal and that has consequences, see a former Federal prosecutor of some note on this subject: http://www.nationalreview.com/article/364117/lawlessness-fix...).
Second, as noted in bmelton's second paragraph, the state insurance commission has to approve the plan. Not only is this sort of thing horrible for Obamacare's economics---there's a reason you're subsidizing others, particularly those 50-64---if they were to allow this anyway, given the best of will by all parties concerned, its highly unlikely they can turn on a dime and get this done in 25 calendar days minus processing time to avoid a lapse in coverage.
Among other things, the insurance company can't afford to offer you exactly the same terms, costs have gone up at least a bit. So the company has to figure out terms that'll likely result in a profit, and the commission has to determine if it's appropriate.
Per Obama's promise not to prosecute, the company also has to have someone smart sit down and detail in every respect how this plan is deems deficient compared to the Obamacare floor. That's more than a tiny amount of work, with potentially severe liability for getting it wrong.
But, yeah, call them and ask them if they're trying to renew your plan and if they think there's any chance they'll be able to do it in time.
It's possible that they can't, and it's also possible that the state of California wouldn't allow them to even if they would (rumor is California was opting out of the delay).
Aside from that, I don't know that there are any great alternatives. The highest-risk gamble is to change your withholdings so that you won't get a refund, and then just take the penalty, which the IRS won't be able to collect as they're only authorized to take it from payouts -- no payouts = no penalty (though if you ever do qualify for a return, it would certainly be withheld then.
The lowest risk alternative is obviously to sign up for ACA, and just really, really hope that you don't need to engage it for services.
Lastly, if it's a serious concern (and it probably ought to be), you could look at getting a job that offers health care as a benefit.