How do I re-engage my disengaged users? Do I duplicate the series and start over?

Help! I have been migrating several campaigns to series and noticed users are disengaging because I was confused by the time limit for matching rules. In campaigns, it seems there was a continuous attempt to match rules. However, in series, you have to specify the length of time. I have gone in and changed all to 90 days, but I am still very concerned about my disengaged users. I need to develop a plan to re-engage them and the best idea we've come up with is to pause current series, duplicate the series, confirm rules are accurate, and then re-send. I acknowledge this may lead to duplicate emails which I will notify our users about.

Any help would be greatly appreciated. So frustrated with myself!