Bottom line: I reached my activation limit way back, at about the same time, the whole activation system changed (it seems the company was bought or merged or something) and so things were changed with the installers and support method.
We never changed any system. Assuming, of course, you are referring to the Zurich scenery, which I guess you are, since you have posted in the Zurich section.
Perhaps, you confused us with Cloud9, because they used our sales system in the past and yes, they have changed policy, switching from 2 activations per order, to 6 activations per order, so now the activation policy for Cloud9 products it's exactly the same as FSDT. AND, Cloud9 ceased operation a few years ago, so we took over their customer support.
However, keep assuming you are referring to Zurich, since this has always been an FSDT product, none of the "system changed" has anything to do with it, because Zurich had nothing to do with Cloud9, and we always had the same activation method and policy, which only matters if you were trying to reactivate a Cloud9 product.
In any case, as clearly explained on our FAQ page, even if you exceeded your activations limit, if more than 90 days from the last activation have passed, a new activation will be granted anyway automatically. Just install the product and activate it with the "Register Serial" function of the Addon Manager.
If, instead, LESS than 90 days have passed from the last activation AND you have used all your 6 activation, a clear error message will say you used too many activations. If that happens, the solution is contact support BY EMAIL, since you can't obviously supposed to share your purchase details on the forum.
If you still have your purchase receipt with your Serial Number, even if the email is not valid anymore, it won't matter, because the only thing the counts it's the Serial Number. However, while you are at it, contacting support BY EMAIL, asking to change your old email with one that works, is something you might want to do anyway, so it will be easier to retrieve a copy of the email receipt, should you ever lose it.
Basically, every question related to past orders, should always use E-EMAIL, not the forum. The contact address is listed on the "Contact Us" page.