[austhrow743]

Sure, I understand that there's a difference. That's why I sought clarification.

My understanding of the concept of "basis" does not fit the context of sending an email, and "reason" is the closest I can find that fits.

Basis being concerned with rules or authority. The assumption being when asking "what is the basis for X?" that there was a bar that needed to be met beyond the doers motivations. That there needed to be more than they wanted to. Which of course, does not apply to sending an email. I could email you right now asking you what your favourite type of fish is or seeing if you want to play a game of chess, no basis needed. I'd just need a reason to.

[cj]

That’s a very intricate and convoluted way of saying they have no basis for making a demand.

But sounds like we agree, they have no real basis for making a demand.

[austhrow743]

Poorly explained maybe but it covers not just that there is no basis but that no basis is needed and draws attention to the odd request for a basis where none is needed.

Just "there is no basis" as a response would be like saying "yes" or "no" to "have you stopped beating your wife?"