n April 2017 Ebay seller lm195902 from Zanesville, Ohio in USA was trying to sell this Indian plate.
He says it is new and he doesn’t really know much about it.
The Registration JRS has never existed in any of the systems in India (1902, 1939, 1947). I think this plate was collected in the 1970s probably and it is just some random registration put on to make it look sort of like a real plate without caring if the registration was possible or not. Possibly the original collector had the initials JRS and 151 was somehow special for him (Jan 1951?).
If you don’t care whether the plates you buy are real or not, this one is for you but this could never have been used in India. Made-to-order special, fake, sample, call it what you like.