First of all, I am sorry for your loss. Unfortuately, there is no baromoter to determine the length of time a lawsuit will take. There are many factors which may effect the length of the suit including, the complexity of the legal questions, the factual scenario underlying the suit and how we wll the parties cooperate . Since, most class action suits are quite complex and deal with so many people, they generally take a bit longer to come to a resolution. Several years would be standard in my opinion. I hope this helps.
I agree that there is really no way to tell. The case could settle tomorrow, or it could go to trial and drag through appeals for many years. There is simply no way of guessing how long it might take. You should know, however, that the class action -- if eventually certified -- may well exclude people who died from the class. I strongly recommend that you contact your local state or county bar association for a referral to a plaintiff attorney who specializes in wrongful death cases...you will likely realize a more substantial recovery than as a member of a class action.