I think you miss-understand. Allow me to explain things:

You purchased a license for DiscBlaze 3.x. Some time later we released 4.x, our first (and so far only) update that we asked users to pay for (2.0, 3.0 and 5.0 have all been free updates).

We offered incredibly cheap discounts for existing 3.x users to upgrade to 4.x for almost a year. Sent out several emails letting all existing users know of the discount and even included information on the discount in several releases of DiscBlaze 4.x and on our website.

The license for DiscBlaze changed during the 4.4 release. So now almost all functions of DiscBlaze are free for everyone without limitation. We offer a handful of the more advanced features as an upgraded, for pay, "Pro" version. Any existing 4.x customer automatically gets access to all those Pro features without needed to pay any upgrade price.

In fact DiscBlaze 5.0 Pro is a free upgrade for existing 4.x and Pro customers as well.

We recently stopped offering the discounted 3.x to 4.x upgrade from our online store... well... because we thought everyone who wanted to upgrade already had.

Though if there are still 3.0 users who wish to upgrade to 4.x/5.x then we can add this option again for a while. Toss us an email with your info and we'll get you setup.