tl;dr: You are *very* likely not affected.
We are planning two changes in the REST API:
1) Remove the experimental /page/html/ and /page/data-parsoid/ listings [1][2]. Our metrics show that these are essentially unused. The same title listing remains available at /page/title/ [3].
2) Make the `tid` path parameter in the unstable /page/data-parsoid/{title}/{revision}/{tid} [4] end point mandatory. Data-parsoid is tied to a specific HTML render, and only requests with an explicit timeuuid from the corresponding HTML response are guaranteed to get the correct data-parsoid version.
If things go to plan, we will deploy these changes sometime next week.
Thank you for your understanding,
Gabriel Wicke for the Services team
[1]: https://en.wikipedia.org/api/rest_v1/?doc#!/Page_content/get_page_html [2]: https://en.wikipedia.org/api/rest_v1/?doc#!/Page_content/get_page_data_parso... [3]: https://en.wikipedia.org/api/rest_v1/?doc#!/Page_content/get_page_title [4]: https://en.wikipedia.org/api/rest_v1/?doc#!/Page_content/get_page_data_parso...
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