My former T would answer my phone calls in the evening and on week-ends. She worked out of her home so she saw clients at night and would sometimes call me back after her last client.

I can email my current T anytime, and she emails me back at her convenience, but usually the same day or the next one. She doesn't want me to call her unless it's urgent, though.

I agree with sunrise: there should be some kind of plan for when you need a question answered about your medications and it's after hours.