Well, the answer to keeping your recordings is yes and no. If you were simply expanding the drive, it would be possible.

If you were interested in the hacks for video extraction, then it wouldn't be a possibility.

I've already expanded the storage capacity, but I purchased a complete upgrade rather than do it myself. It was just easier to pay and additional $30 or so to have to do nothing beyond plug the drive in.

However, what if I just wanted TivoWeb for its other features besides video extraction? Would installing it by itself, without extraction capability, require making current recordings unusable?