Is it possible to set up a redirect from a tilda.ws subdomain to another domain?
When connecting a domain in Site Settings → Domain, for the old website address on tilda.ws with HTTP (http://test.tilda.ws) by default redirect with code 301 starts working, but under the condition that in the site settings → SEO → redirects for WWW, HTTPS redirect from the address with WWW to the address without WWW and from HTTP to HTTPS are set.
The website is always available at the tilda.ws address, but this address is not indexed by search engines after a domain name is connected in the Site Settings since the canonical address will be the address with the connected domain.
Further information about the canonical address is available at the following link: https://help.tilda.cc/search-engine#double-url
The maintenance addresses on tilda.ws (project123456.tilda.ws and subdomain.tilda.ws) can be indexed before a domain name is connected to your project. In this case, the maintenance addresses of the website will disappear from the search results once search engines update the information about your website.
Also, you can try to force the removal of unnecessary page addresses from the search with the following guide from Google.