In order to set a redirect from Acast, you'll need to contact Acast support to help set up a redirect. Acast support can be reached at firstname.lastname@example.org. Feel free to utilize the follow email template:
Hi Acast Support,
I'm moving my podcast to a new hosting provider. Please apply a redirect for my show - [Your Show Name]
Can you please apply a 301 redirect from [Insert Acast RSS Feed] to [Insert New ART19 RSS Feed]
Please let me know when this is complete.
Once Acast support confirms the redirect is set your series should be redirected to its new ART19 RSS Feed. Additionally, if you need help finding your ART19 RSS Feed please reference this help center article.