Synonyms for Probationary:

adj.

•all (adjective)
provisionary, provisional, tentative.
•experimental (adjective)
provisional, tentative.
•tentative (adjective)
acting, provisionary.

n.

blue-collar, emeritus, creative, designate, auxiliary, acting, deputy, budding. associate, assistant, cooperative, collaborative, collegiate, casual, ceremonial, clerical, adjunct, antisocial. •probationary (noun)
conditional, provisionary, tentative, provisional.

Other synonyms:

•tentative
tentative.