Just to clarify, it isn’t by when you booked your seat, but what category of fare you bought & when you purchased the EBCI.   Someone could have booked their WGA  ticket on release day, but not purchased EBCI until a week before their flight.  They’d always be behind everyone with BS, Anytime, A list, WGA+.  But they’ll also be checked in behind anyone with a WGA ticket that bought EBCI before they did. So to your question, if you have WGA tickets, you will be behind all those other fare categories & anyone else with a WGA fare who purchased EBCI before you.
How close is your trip? If it’s just days away, you may be only a few slots in front of people without EBCI.  Is that worth it to you?  Some people think it’s not worth it & just take their chance at checking themselves in.  Another option may be to upgrade your husband & 9 yo’s boarding position at the 24 hour mark.   NOTE: this  option MAY or MAY NOT be available.  If  there are any spots open in BS, A 1-15, they’re offered as upgraded boarding.  From my city it costs $45.  The option is bookable online at the 24 hour mark, right as  you check in if it is available.   It is a gamble if it will be available of course, but it’s another option.