New julia 1.7 install with jill: how transfer julia 1.6 packages (macos)

General Usage
2

If your packages are in the default environment, you should copy ~/.julia/environments/v1.6 to v1.7:
E.g.
cp -r ~/.julia/environments/v1.6 ~/.julia/environments/v1.7

Also, from here it looks like if you do

jill install 1.7.0 --update

Jill will do that for you.