> In GNU Emacs 27.0.50 (build 1, x86_64-w64-mingw32)
>  of 2019-09-19 built on CIRROCUMULUS
> Repository revision: 61c2183a440c94ab797696d0f0c76a7dc4007eeb

That revision is more than three months old:

 commit 61c2183a440c94ab797696d0f0c76a7dc4007eeb
 Author: Phillip Lord <phillip.lord@russet.org.uk>
 Date:   2019-06-04 15:02:33 +0100

Could you please try with a recent snapshot from master?

Also surprising:

> Configured using:
>  'configure --without-dbus --host=x86_64-w64-mingw32
>  --without-compress-install -C 'CFLAGS=-O2 -static -g3''

I thought Emacs could not be cross-built. Are you crossbuilding from Windows to Windows (assuming that's even possible)? Why?

Do you happen to have a non-standard lisp/loadup.el perhaps?