Is it any propagation delay when changing custom domains in Branch.io

For a couple of years, we had links.customdomain.com assigned into production application in Branch.io service as a domain used to route deep-links.

We have approximately ~20_000_000 links created though Branch API on https://api2.branch.io/v1/

We changed our domain links.customdomain.com into links.newdomain.com and expected that all old link will work the same way new the new domain (aliases are saved but only changed domain), e.g.:

• Old link https://links.customdomain.com/alias/hash works on https://links.newdomain.com/alias/hash

But after changing, we do not see that old deep-links aliases works on the new domain.

Are there any propagation ETA or all old deep-links are invalidated and deleted after changing custom domain?

When you change assigned domain, all old deep-links will be assigned to the old domain and they will became unavailable.

If you want to keep all old deep-links available on the new domain - write migration to re-create those links