Date fields

I have a file with a date in the filename and nead to calculate a future airing date from it. Is it possible to $add to date fields and will it follow the calendar. Files only come weekdays.
Eg xxx 20170602 - Aug 01 - etc

  xxx 20170605 - Aug 02 - etc


Yes, you can use the $add function to add values.
No, MP3tag does not know anything about dates, you would have to take care about that yourself.