Hi,
I haven't found any specific documentation but looking in the MYSBootloader's code I found this two checks in HW.h (https://github.com/mysensors/MySensorsBootloaderRF24/blob/development/HW.h)
#if defined(SPI_PINS_CE9_CSN10)
..
#elif defined(SPI_PINS_CSN7_CE8)
..
#endif
does it mean that those PINs (9+10 or 7+8) are the only options to have MYSBootloader on Arduino boards? (obviously without modifying the code and recompiling..)
thanks
Max