The texture for Red Sandstone Stairs for some reason appears to be rotated (facing north, south, east, west) based on the coordinates of where it is placed, and the block's actual orientation has no affect on it's texture. No other stair has a rotating texture, nor do any other stairs have this problem (as far as I have seen).
How to replicate: Place multiple of the "Red Sandstone Stairs" block facing the same way, then compare the textures between each block.
Note: This affects all texture packs and the default textures, however it is more noticeable in certain texture packs than in others, as such I have included a second image of the same blocks in a texture pack other than the default.
This also affects multiple platforms but I don't know how to list more than one.
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-20677.
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