When I run the program, only boss1@gmail.com gets bcc\'ed.
I\'ve debugged the program and each variable is logged correctly.
MailApp.se
Send emails with multiple cc / bcc addresses.
From the "Advanced parameters" section of sendEmail documentation:
a comma-separated list of email addresses to CC
This means we can concatenate the variables and separate them with commas using the + operator to achieve your goal.
MailApp.sendEmail(
EPEmail,
"Internship Opportunity at "+OP,
emailText,{
cc:Manager1+','+EPManager2+','+EPManager3,
bcc:Boss+','+"boss1@gmail.com"}
);