Almost all of the previous deploys for my site have disappeared

[SamO]

We started a process where we delete old deploys longer than the last 90 days.

By default, Netlify will delete deploys after 90 days. Netlify will not delete the deploy currently published to your site (also called the published deploy), or the most recent successful deploy from a Git branch.
Here is some recent info we published about this change in effect since October of 2022:

Automated deploy cleanup and new deploy retention policies starting late October 2022

Starting no sooner than October 25, 2022, Netlify will begin automatically batch-deleting non-critical deploys older than 90 days. Alongside this release, Netlify is also introducing new, configurable deploy deletion policies for customers on Business and Enterprise plans who may want to keep deploys for longer or delete them more frequently. [A policy to delete deploys after 1-365 days] Automatic deploy deletion will not impact your production site or your underlying source code hosted by yo…

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