Redwood migration with just 1 dev environment

Hello,

with a specific client we only have 2 environments, Production and TEST.

Since we are going to make migration to Redwood, we would like to to understand if it's safe to go with the first migration testing with only the TEST environment available, which will also be the base for every regression test in the next months after every new release.

Do we need to have another environment? (dev1)

Do we need to follow any good practice?

Thanks