XandVich sudoku Hint #9

[billiswow]

I'm working through this puzzle, and all makes sense apart from 'R5c7 must be from the other flavour of 2/8 or 3/7' Could anyone help me out with why? I can't figure out the logic behind this and wondering if I'm missing a technique. Thanks!

[Mojo]

I'm stuck at the exact same part!

[Mojo]

Ok, figured it out. The '25' sandwich hint in column 7 forces R1C7 and R9C7 to add up to 10. We know the flavour of R9C7, and now R1C7 has to be the same flavour. And now due to sudoku R5C7 is forced to be the other flavour.

[billiswow]

Nice one, well spotted :)

[ScarlettOverflow]

Thank you for this! I totally forgot about the sandwich rules by the time I was this deep in