Transforming keys in Sequencer changes the interpolation of the keys

Going over the new features for 4.15 and I noticed that adjusting the transform of the keys in Sequencer, causes them to change to a linear interpolation. This is also effected if you select Transform through the Select/Edit Option menu in Sequencer and adjust the transform from there.

Workaround Right click the key and select Cubic (auto) again to set the interpolation back to default

1. Open any project
2. Create a new Level Sequence
3. Add a cube to the level sequence at transform X:0 Y:0 Z:0
4. Set the transform key at 0 in the sequence
5. Scrub to 30 and set the transform to X:0 Y:210 Z:180 and add a key
6. Scrub to 60 and set the transform to X:0 Y:410 Z:0 and add a key
7. Select all 3 keys and hit Ctrl M
8. Press the + in the transform option UI that appeared when Ctrl M was pressed

Result: The interpolation of the keys changes to Linear, but the UI remains Cubic

Expected Result: The interpolation does not change in the sequence