It's been a while ... but
Don't gloss over how long it has been, instead, recognize it with respect
Have you ever received a message from a business associate, brand, or vendor that started with, "It's been a while, but ..." where they then launch into a pitch of their new product or service offering?
How does that make you feel?
The, "It's been a while" part should not be glossed over. A lot has probably happened since then.
Staying in touch with everyone in your address book may not be feasible, but reconnecting with them with a sales pitch is the wrong way to do it.
Instead, rekindle the relationship with something of value. The equivalent of showing up with flowers.
It may have been a while, but we still deserve respect.
When looking at the screen, it is easy to forget we are doing business with real humans.
All the best,
P.S. I am pondering launching a newsletter school. Are you or someone you know interested in using newsletters or email in your marketing efforts?