Sleep Appliance

Hey, so I got diagnosed sometime around August last year, and it's been a nightmare trying to get a sleep appliance I finally had the initial appointment today where the new dental office gave me the thing to reset my mouth in the morning and then told me the earliest they could do was sometime in late August because the specialist is away. I asked if there was an exception they could make and maybe get the appointment done with a different dentist or anything, but they told me no. Looking for a second opinion on what to do because I am beyond frustrated. Just take the date they give, or do I ask for the scans and try my luck with another specialist?