I prefer after and next - it's way more natural. I prefer email. E-mail is a bit old-fashioned.

Yes, no way out!!

It appears the consensus is 'next' and 'email'. As for 'when' or 'after', either is fine, but I prefer 'when'; it's more specific. 'after' is open-ended. How long after the package will you send the email? 'when' means "exactly when you send the package (or not long after) you will send an email." Hope that helps!

‘When’ and ‘after’ have different meanings, as do ‘second’ and ‘next’. So it’s a matter of meaning, not preference. There are several ways of conveying a similar but not identical meaning. I’ll email you after I send the package. (Send, then email some unknown time later.) I’ll email you when I send the package. (At the same time) I’ll email you after l’ve sent the package. (Send, then email some unknown time later) I’ll email you when I’ve sent the package. (Send, then email immediately) Of course, the context might tell you how much later is implied by ‘after’. As far as a passive construction: I’ll email you after the package is sent. (This is fine, too. But unless explained by the context, someone else could be sending the package.) ‘Next’ tells you that one or more packages have already been sent. ‘Second’ doesn’t. I’ll send you three packages every day. I’ll email you when I send the second package. (‘Next’ doesn’t make sense) ‘E-mail’ is older. I prefer email.

After for sure, next package or second, third and so on and email or e-mail Greetings Tim