No they won't, the existing copper coax cable is more than capable of running at 350 Mb/s. In reality, the term 'fibre broadband' is a bit vague and tends more to a marketing strategy rather than any technical differences.
DOCSIS 3.1 over coax can go up to 10G, download and 2G upload.
Tudor There are 10 types of people: those who understand binary and those who don't and F people out of 10 who do not understand hexadecimal c1a2a285948293859940d9a49385a2
VM does not in any case use "copper coax" as although the coaxial cables between the optical nodes and premises have copper coated cores the copper is just for shielding from interference and thus carries no signals.