Helping my daughter and friends get their 2nd vaccine

My college age daughter and friends are driving across the country. They started in VT and are now on Colorado. They managed to get their first dose of Moderna today in Arizona. While they did make their 2nd dose appointment before they left, they will be heading to Oregon in. Few weeks, then winding their way back to NH by June. They would have to make a special trip to AZ from Oregon for their second dose and would prefer to do it locally, while in Oregon ( they plan on being in Oregon from Apr 18 til early May.

At the moment they are not eligible to sign up in Oregon; not til May 1. Trying to help them out and wondering if anyone has some good advice on this matter.

Thanks!