[tex-live] Testing and Upgrading on Windows

[texlive.jlists at spamgourmet.com]

Hello all,

sorry if the answer to this question can be found somewhere obvious - at
least I could not find it.
Is it possible to test the prerelease of TeXLive on Windows by "upgrading"?
I have read that it is yet to be decided whether there will be an upgrade
script for Windows. - However, on the TL lists, there is frequent mention of
one; in particular, it supposedly updates TL during pre-release.
Or is this a big misconception and I should simply do "tlmgr --update
--self" against the prerelease repository?

Thanks in advance,
Dominic