There is no requirement that a deposition be taken. If the insurance wants one, they should have a reason...something they want to find out about. Maybe there is something in your case....and maybe not. In any event, the depo is not designed to help you. They're don't sit down and say, "Mr. Laguna Niguel has a $10,000 case, let's take his depo and see if we can justify giving him $15,000!" No. More like, "How can we get that $10,000 case down to $5,000? Let's hire an expensive lawyer to take his deposition (which will cost us several thousand dollars) and see if we can save some money." So don't be looking forward to having your deposition taken.
Assuming that the deposition is going to be taken, it can be at any time during the case. From 3 weeks after you file your claim to 3 years later.
If your deposition is scheduled, you really don't want to go into it alone. You really want to have an expert by your side to protect you. That expert is called an attorney. The insurance has their expert. Do you really think you can beat him at his own game? Not likely. Find a good w.c. attorney here at www.avvo.com or at www.caaa.org. CAAA is the association for attorneys here in CA who represent injured workers. Or you can call me for a referral. Good luck.
Deposition cannot happen unless someone files an Application for Adjudication, and gets Case # ADJ9999999 assigned. Either your Attorney did it, or the Ins Co did it. If the Ins Co files the Application before you get an Attorney, they have to pay your Attorney Fee on top of your settlement.
We give free general concepts to be helpful, but you should give ALL your facts to a licensed Attorney in your state before you RELY upon any legal advice.