Traveling while EAD application (for H4 visa holders) is in process

My wife is an H4 visa holder. And we have applied for her EAD (i765 on basis of an I-140 approved spouse) as per the new immigration rule from USCIS.

Can the applicant leave the country on vacation while the EAD application is pending?

Considering the adjudication of such cases is taking a lot of time these days, we filed for EAD last month and we are planning to go for vacation around the month of December. While being hopeful that EAD will be approved much before that, I wanted to understand

  1. If it’s allowed to leave the country

  2. What all could be needed: RFE, fingerprinting etc. while we are away and if such can be rescheduled?