It hasn't been limited to probationary employees. Here's one example: https://www.science.org/content/article/nih-ban-renewing-sen...
Agencies have also been directed to make plans for "significant reductions". For example, EPA plans to cut 65%. Fish and Wildlife and the Bureau of Indian Affairs are preparing for up to 40%. These latter cuts haven't happened yet, but they're very likely.
That's correct. It hasn't been limited to probationary employees only, but many are. Those who are not either aren't needed or will be rehired if operations cannot continue without them.
