Sorry you can't make it opening day, thats a bummer

But ya gotta do what cha gotta do.
I have been in this situation before myself.
And if I were you,I would takeasmuch time as possible to find where several different birds were using.
This is a good idea anytime,

but especially when you gotta miss those first days.
Alot can happen during those days, when you're not there.
Someone could kill the bird your scouting.

Hunting pressure could change bird patterns.

Your bird could walk in on another hunters call and become call shy.

Of course alot of this depends on if your on public or private land.
Anyway, if I were you, I'd have a backup plan just in case..