DEV FROM ASSIGNED ALT.

Narrative

OUR ACFT WAS CLRED TO LEAVE 12000 FT AND CLB TO 17000 FT. AS WE PASSED THROUGH ABOUT 14000 FT ATC CALLED VFR TFC AT OUR 1 O'CLOCK POS AT 15500 FT. EVEN THOUGH THE TFC WAS OPPOSITE DIRECTION; NO TURNS OUR ALT RESTRICTIONS WERE GIVEN TO US TO AVOID THE TFC. WE DID NOT CALL TFC IN SIGHT TO ATC. AS WE CLBED THROUGH 15000 FT WE SAW TFC AND INCREASED OUR RATE OF CLB TO FOLLOWING THE TFC ON THE TCASII SCREEN. WHILE WE AWAITED INSTRUCTIONS FROM ATC TO AVOID THE TFC IT BECAME OBVIOUS WE WERE ON OUR OWN. OUR ORIGINAL RATE OF CLB WAS 2000 FPM AND THIS WAS INCREASED TO +4000 FPM. WE AVOIDED TFC BY MORE THAN 500 FT VERTICALLY AND 1-2 MI HORIZ. OUR HIGH RATE OF CLB AND CREW CONCENTRATION ON THE TFC CONFLICT CAUSED US TO OVERSHOOT OUR CLRNC LIMIT OF 17000 FT BY 300 FT. WE NOTIFIED ATC OF THIS OCCURRENCE AS A TCASII TA. ATC WAS NOT BUSY ON THIS FREQ AND SEEMED TO BE NEGLECTING OUR SITUATION. THEY SAID NOTHING FURTHER ABOUT THE OCCUPANCE AS IF IT NEVER HAPPENED. AFTER ATC INITIALLY CALLED THE TFC LOCATION THERE WAS NO FOLLOW UP INQUIRY AS TO WHETHER OR NOT WE HAD THE TFC IN SIGHT. THERE WERE NO VECTORS GIVEN TO AVOID TFC AND WE HAD BEEN CLRED THROUGH HIS ALT ATC DROPPED THE BALL ON THIS 1.