It may or may not be true, like my friend had said, if one day Windows was defaulted to be installed/booted on REFS(or a new FS), then it couldn't be an "Windows 10 Update".

Some guys asked me about the "16 thing" in Windows RTM no., I've posted about it in Neowin when win7 RTM'ed at 7600, so briefly: Windows Team need to reserve some places for SP's, the binary string of Windows builds consists of a string of 14 bits to represent the build no., so what they did was that, for the RTM build, the 1st 4 bits have to be 0, as 2^4=16, so there are 16 nos. reserved for SP's, the RTM itself is SP0, also, no matter what's the combination of 0 and 1 for the 5th to 14th bit, the number this string represents would be a multiple of 16, it's that simple. In Vista time, the head of Exchange(forgot his name) became Windows head, and he likes major builds to be ended up in "00", and set the rule that RTM nos must be multiple of 100, so, along with the "16 rule", RTM nos must be a multiple of 16 and 100.