As we near the final stages of the Pretrain project a wider group of people will be impacted by the changes that the new deployment will bring. We spent a lot of time talking about what the hard requirements were in T379683: [FY24-25 WE6.2.6] Create design document for Pretrain (née Group -1) deployment which led to documentation in https://www.mediawiki.org/wiki/Wikimedia_Release_Engineering_Team/Pretrain#Design_agreements and various gdocs. Now we need to socialize the general changes with the larger community.

As things move from theory to practice moving testwiki from group0 to pretrain will have some impact on:

• SREs who respond to system overloads and outages
• QA specialists who perform manual and automated testing against testwiki today
• QA specialists who perform manual and automated testing against Beta Cluster today
• Community members who test things against testwiki today
• ???

Change can be scary, so we should do what we can to help folks feel confident that these changes are actually good. There is a lot of narrative on https://www.mediawiki.org/wiki/Wikimedia_Release_Engineering_Team/Pretrain already, but it may be possible to make it easier to read through. We should also be able to start a FAQ for various questions like "How will group0 deployments be tested once testwiki is in pretrain?" Once we feel that the mw.o page is useful we should post to wikitech-l and elsewhere to let folks know these changes are coming so that there is time for a normal cycle of concern, information gathering, and acceptance.