ATL TRACON CHANGED A CRJ700 FROM RWY 28 TO 27L. AN FMS DISCONTINUITY CAUSED BY THE RAPID RTE CHANGE WAS NOT CAUGHT BY THE CREW RESULTING IN A TRACK DEV.

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ON THE HONIE 5 ARR INTO ATL; ATC SWITCHED RWYS FROM RWY 28 TO RWY 27L. COPLT ENTERED THE NEW RWY INTO THE FMS. I WAS FLYING AND APPROACHING FOGOG INTXN. AFTER CHANGING RWYS IN THE FMS; WE DID NOT CHK THE WAYPOINTS AND WE HAD A 'DISCONTINUITY' AT FOGOG. THE ACFT OVERFLEW IT AND DID NOT TURN US DOWNWIND. WE NOTICED IMMEDIATELY AND ATC QUERIED US ON THE RADIO. I DISCONNECTED THE AUTOPLT AND TURNED TO REJOIN THE ARR. ATC DID NOT SEEM TO BE CONCERNED.SUPPLEMENTAL INFO FROM ACN 778970: THE CTLR DID SAY 'EXPECT SHORT APCH;' BUT I LOADED THE FIRST WAYPOINT JUST IN CASE WE NEEDED IT FOR EASY RETRIEVAL. WE WERE GIVEN THE INSTRUCTION TO EXPECT '27L' AT LEAST 5-10 MI FROM FOGOG. I CHECKED ALL THE WAYPOINTS ON THE ARR TO VERIFY THAT THEY WERE CORRECT AND HAD NOT BEEN DROPPED OUT AFTER THE EXECUTION OF THE NEW RWY. THE MFD ALSO SHOWED THE APPROPRIATE COURSES FOR THE ARR AND THE AUTOPLT WAS IN FMS MODE TO FLY THE ARR. WHEN WE WERE GETTING CLOSE TO FOGOG I NOTICED THAT THE AUTOPLT WAS NOT USING 'TURN ANTICIPATION' TO BEGIN THE TURN EARLY SO WE WOULDN'T FLY THROUGH THE NEXT COURSE SINCE THERE WAS A TURN AT FOGOG. I POINTED IT OUT TO THE CAPT AND HE MANUALLY DISCONNECTED THE AUTOPLT AND EXECUTED THE TURN HIMSELF. I CAN'T REMEMBER HIS EXACT WORDS; BUT THE APCH CTLR DID QUERY US BY SAYING SOMETHING SIMILAR TO 'YOU ARE TURNING ON THE ARR THERE AT FOGOG AREN'T YOU?' SINCE I WAS THE PM; I SAID 'YES SIR; THE AUTOPLT SEEMS A LITTLE SLOW ABOUT MAKING THE TURN SO WE ARE HELPING IT OUT.'