Hi all,
Have been in touch with the WMF and ORG on this in the past months asking about this. Current status is that the WMF took the lead and will prepare a submission document for the UK government. They are working with WMUK and keep us from the FKAGEU a.k.a. wikimedia.brussels in the loop, which I am grateful for.
On a more general note, we can already observe that Brexit in practice means more work on most policy files. This is because the UK government seems to work in parallel to the EU legislator on many issues. If the EU does something on content moderation, so will the UK. If the EU does something on digital markets, so will the UK. To be fair, France and Germany do something similar by trying to "pre-transpose" parts of future EU laws in order to set a trend.
Cheers,
Dimi