ghc-pkg mismatch with ghc-9.0.1-alpha1

I installed ghc-9.0.1-alpha1 using ghcup.

Running cabal new-configure -fdev -froundtrip --enable-tests --with-compiler=ghc-9.0.1-alpha1 on ghc-exactprint gives

cabal: Version mismatch between ghc and ghc-pkg:
/home/alanz/.ghcup/bin/ghc-9.0.1-alpha1 is version 9.0.0.20200925
/home/alanz/.ghcup/bin/ghc-pkg is version 8.8.4

Note:

$ ghc-9.0.1-alpha1 --version
The Glorious Glasgow Haskell Compilation System, version 9.0.0.20200925
$ ghc-pkg-9.0.1-alpha1 --version
GHC package manager version 9.0.0.20200925