abreast vs up on

abreast and up on both are adjectives.

Word	Noun	Adjective	Verb	Adverb
abreast	No	Yes	No	Yes
up on	No	Yes	No	No

As adjectives, abreast and up on are synonyms defined as:

abreast and up on: being up to particular standard or level especially in being up to date in knowledge

Other synonyms of abreast include au courant, au fait.

abreast (adjective)	up on (adjective)
being up to particular standard or level especially in being up to date in knowledge	being up to particular standard or level especially in being up to date in knowledge

abreast (adverb)	up on (adverb)
alongside each other, facing in the same direction