Just for future record, my suspicions were correct, I installed the drive into my PC (connected it to a sata cable instead of the external USB 3 drive bay) it formatted in several hours. Lesson learned, I shall install larger drives inside the case in future then add them to the drive bay once formatted. I always full format a new HDD, can't always trust Yodel drivers, plus the box had clearly taken a knock at some point.
Begining to think I should have installed my HDD inside the PC to format it. I have put a new 10TB HDD into a Yottamaster USB 3 drive bay, it is running through a UGreen USB 3 Swapper into a USB 3 port on back of my PC. Could this be why it has only formatted 13% in 24 hours? Should I cancel the format, install the drive inside the PC, connected to Mobo, and format it, or will this make little difference?