I downloaded the firmware files per the links provided (RBS50-V2.1.4.10-0430-dbg.img and RBR50-V2.1.4.10-0430-dbg.img). However when I go to upload load (I am using the manual firmeware instruction provided) the satellite formware I get the following message:

This firmware file is incorrect! Please get the firmware file again and make sure it is the correct firmware for this product.

My router and satellites are on V2.1.4.10 currently. Any ideas? I have 35 homekit device so this issue is killing me.