The California Family Code is not explicit on this situation, however, your filing of an amended petition essentially nullifies the original petition that was filed 12 years ago. There are now new "allegations" that must be answered to. In the eyes of the law, the amended petition is an entirely new document which resets that clock. You should expect the six month waiting period to begin when service of the amended petition takes place or when your spouse "appears" (i.e., files her response), whichever occurs first.
Because there was no proof of service, I believe the 6 month period will be effective once he has official notice of the amended petition.
The 6 month period will start from the date you spouse is properly served with the amended petition or the date your spouse responds to the amended petition. To be clear, the 6 month period has to do only with the earliest date by which you can be deemed legally divorced (i.e, single for purposes of remarriage). If you have an agreement, and this will not be a contested divorce (court battles), you should be able to complete your process in a matter of weeks or months, rather than years. Once you have a signed judgment (signed by the court) and the 6 months have passed (from the date your spouse was served with the new petition or responds to the new petition), you will be divorced and free to remarry. That is the significance of the 6 month period.
My suggestion would be that you have an attorney prepare all of your documents (many of us do this on a flat rate, limited scope basis) so that you get everything properly done and do not have prolong it any further.
I hope this information is helpful to you. Good luck.
Since the information provided in your question is very limited and I have not had an opportunity to review all relevant facts, information, and documents, you should not rely on any specific responses to your questions. The information offered here is general in nature given that the slightest bit of additional information could change a specific answer (i.e. we separated 1 year ago and he has been paying all my expenses. Q: Do I owe him that money back? A: Yes. But what if he used money from a community asset, like a retirement account, to pay it back. A: maybe some or maybe none). In short, consult an attorney to review all relevant information so s/he can properly and accurately advise you. This free service IS NOT a substitute for legal advice and should not be considered legal advice at all.
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