Migration, Nameserver question

So, I’m migrating a WordPress site from its test location on one domain to its home domain while changing hosting companies for its destination domain.

I’ve already uploaded the latest version of WP to the destination server and initiated the DNS transfer of the domain. I understand it can take 1-2 days to complete the transfer.

Can I continue with the process (changing the addresses in the dashboard general settings, backing up/restoring the database) while the domain name still points to the old site or do I have to wait till the transfer goes through?

Thanks.