What rights and protections do Schedule A employees have…?

...particularly if you're a probie or are RIF'd???

Per OPM's exisiting explanations of Schedule A:

Excepted service appointing authorities are critical tools for increasing employment opportunities for people with disabilities in the Federal Government. Two of these authorities are particularly relevant:

Schedule A, 5 CFR 213.3102(u), for hiring people with severe physical disabilities, psychiatric disabilities, and intellectual disabilities. This excepted authority is used to appoint persons with severe physical disabilities, psychiatric disabilities, and intellectual disabilities. Such individuals may qualify for conversion to permanent status after two years of satisfactory service. Severe physical disabilities include but are not limited to blindness, deafness, paralysis, missing limbs, epilepsy, dwarfism, and more. Schedule A, 5 CFR 213.3102(ll) for hiring readers, interpreters, and personal assistants. This excepted authority is used to appoint readers, interpreters, and personal assistants for employees with severe disabilities as reasonable accommodations.