Split Animation does not show all frames in file

I have an animation file(FBX) that has several animations in it, however when i try to go split them into clips, unity will not let me create new slips outside of a certain frame range (249 seems to be where the bug starts). the first clip made in the file correctly has the full range but creating new clips limits it to 249 at the end, even though there are frames after that. it will not let me move the slider past 249, nor can i manually input the frame numbers for start/end as after i hit enter, it just replaces the value with 249.

18280-split-1.jpg

this ended up being a blender issue exporting default take with different end times than other takes.