My Spouse is on H1 and i am on H4, our visas got recently extended here in US. Are we eligible for DropBox

Hello,

My Spouse is on H1 and i / Kids are on H4, our visas got recently extended here in US. Now we are going for vacation, i hear we can do a drop box for stamping ? Also, my wife got converted to Full time for the same client, as now the employer got changed in 797, is that be a good to opt a Drop Box ?

Can anyone suggest the Dropbox options ? are we eligible for this ? i hear we are eligible but dont know the consequences.