How do they get help with those services currently? At present they operate during the same hours those people are working in, shifting the hours makes no difference to them. So this plan changes nothing for them, but is beneficial for everyone else. I welcome suggestions on how to improve it for cusomer support reps too.

I've worked in a "first line of customer support" role, while simultaneously being a customer. Whenever I needed help with something, with my end-user hat on, I knew who to ask internally to get what I needed.