RBK753P work with older RBS50 Satellites?

So,  I have 2 RBk50  routers (1 came with an additional satellite I purchased) and 2 RBS50 satellites.  Lately I have had dropping connections with my ISP quite badly.  Both routers exhibit the same problem.  They provided me with their router to test and I don't have the problem. I am guessing the Routers are EOL with fireware that will not be updated. I am on a M4 Mac with Sequoia 15.2. but not sure that is relevant.  I am wondering if an upgrade is in order for the router to RBK753P.  My ISP is radio frequency to an antenna and my max speed is 70 Mbps so the difference between 5 and 6 is not going to matter, AFAIK.  

At the same time, I am wondering if my existing satellites will work via the mesh  and no Ethernet cable with the new router, or will they need to be replaced as well.

Any suggestions? Ideas? 

Thanks

Jeff