Hire an attorney if you are served with papers. The battle ground is here. He may be just blowing hot air and there are actions that can be taken if he tries to get visitation or custody here.
My offices does represent people from Avvo if they contact me but only in the Los Angeles, Orange, Ventura, San Bernardino and Riverside County in Southern California. The answers I give here are not meant to create an attorney client relationship. When accepting clients I conduct interviews face to face and they often take 30 minutes or more. I approach trials and issues from a legal and common sense approach, This is how the majority of judges I have appeared before in 40 years also make decisions. I do not intend by my advice to enter an attorney client relationship and in most cases advise to obtain legal representation. Sometimes if you can not afford it a consultation or limited scope representation is available. As an experienced attorney I can tell you, judges can be impatient, hate emotional arguments and over exagerations or lies. A brief outline of the problems and desired solutions is often best and I d0 limited scope representations advise clients on how to proceed at time of hearing or trial and my fees are considerably less when I do not appear in court as it takes much less of my time.
You should consider going into Court prior to the expiration of the current restraining orders to have them reissued. Other than that, if he files an RFO for modification of custody, you should retain an attorney. Based on the facts you presented, I don't believe that he will get significant custodial time, but perhaps some visitation.
If you have a 10 year RO then why is he contacting you during the period of the RO? If he is allowed to contact you by text or e-mail, to ask about the kids, I am sure a court said that he could not threaten or harass you. This by definition is a violation of the RO. If he was not given any ability or allowance to contact you then he has been violating the RO on numerous occasions. You should immediately file a police report and charge him with violating the 10 year RO. In California that alone is a misdemeanor. If he is on probation or parole, it is also a violation of his probation or parole. If not, you can bring charges and the county DA can file new criminal charges. The other issue of him getting custody is an issue for Family Court and he can always hire an attorney to file for visits and later custody. I highly doubt that he could get custody without having seen the kids for 10 years. He would start with visits and hopefully monitored visits. You need to hire an attorney to advise you of all your options.
This information is not intended as legal advice and is intended only to provide the questioner with general information. This is not intended to answer any other questions with similar facts. This is a general answer and does not create an attorney-client relationship or an attorney-client privilege.