From the below details of the email thread, it was decided that @RobH would file this task on behalf of @Luky001, but no work would progress on this until after January 3nd, 2020. (WMF goes on code freeze / holiday break starting next week until then.) At that time, @Luky001 will comment with details (including new name servers) to get this moving.
We received an email to the dns admin alias regarding the wikimedia.sk domain.
> I am writing to you on behalf of Wikimedians of Slovakia User Group. Our website runs on wikimedia.sk domain and we are going to be moving to a new web hosting soon. That is why I have a few questions:
> * From the moment I will ask you to redirect DNS, how quickly can you do it?
> * Can you change DNS back to the original state as it is now if something would not work out with the new web hosting?
> * What are your working hours (this and next week)?
> Have a nice day,
@robh investigated, and found the following:
* the wikimedia.sk domain is owned by Wikimedia, but we're redirecting nameservices to third party nameservers: ns.mastersdns.com
** This means that Wikimedia isn't handling DNS services, but this third party nameserver that is likely controlled by Wikimedians of Slovakia User Group (uncertain at the time of this task filing)
** The nameserver setting can be changed by Wikimedia to point to a different name server, but this can only take place during normal US business hours (as our registrar is based in the US).
** It is recommend that the TTL be set to a very low setting (perhaps 5 minutes) for ALL DNS settings for the domain during the migration. This will dramatically increase DNS requests (as the caching for them is low), but will allow any changes required to the domain settings itself to go quickly. Please note that WIkimedia Foundation does NOT handle the dns settings for this domain, ONLY the nameserver settings.
From the above summary of the email thread, it was decided that @robh would file this task on behalf of @Luky001, but no work would progress on this until after January 2nd, 2020. (WMF goes on code freeze / holiday break starting next week until then.)