Can Frame offset still be used if you keyed the frameExtension attribute in image plane?

[yann19]

I could not find much info when doing a google search, but in the imagePlane attributes, can `Frame Offset` still be used if I have made keyframes in the `Image Number aka .frameExtension` attribute?

The reason I asked this because, the Frame Offset is not working properly for me. And hence would like to know if that is by design (the above scenario I have given) or if it is my Maya session, workflow or other issues that could be causing issues with it...