Slanted rails cannot be pulled horizontally by sticky pistons and instead break and drop as an item, see Figures A and B. This issue does not affect rails that are 'flat,' as shown in Figures C and D, or sloped rails that are pulled down, as shown in Figures E and F.

I don't see a link's field before I create this issue so I"ll keep it here: This issue may relate to MC-204889 and MC-2023; however, this is a different scenario to MC204899 and I do not see any 'ghost blocks' as referenced in MC-2023.