EDIT - Perhaps you are confused about why your system went into Eval mode. It went into EVAL mode because you are using a version that you are not licensed for. This is because you installed a version of the software that was released after the initial 12 month support/upgrade time frame you paid for. It's no different than running a demo version on a clean machine (ie no BI software previously installed). That demo version will stop working at that end of that eval period of time. HOWEVER, you can simply roll back to the last update that was released during your initial 12 month support/update time frame and the EVAL will disappear because you will be back to running a version of the software that you ARE licensed for. That original license you bought is a lifetime license and will work forever and never require you to pay more money to make that particular version work in the future. I thought I should make that crystal clear before moving on to my original post.
ORIGINAL POST - That's exactly right. You paid for whatever the current version was at the time of purchase and also got 12 months of upgrades/support as part of that price. You can continue using that version and any update that was released during your 12 months of support/updates forever without paying any additional money. There is no subscription requirement for your software to work.
This is where you are wrong. Perhaps you should have read the terms a little more closely before purchasing the software. You purchased the current version (at time of purchase) and got 12 months of support/updates included. You did not pay for lifetime updates of the v5 software. If you want to upgrade your BI version to a version that was released after the 12 months of support/upgrades that were included in your original purchase price, then you need to pay another annual fee. The new 12 month of support/updates starts from the day you make the new purchase. It does not attempt to "clawback" any previous timeframe that you were not paying for support.
I've dealt with companies that did offer "lifetime" updates of the current version and I don't like that model at all. First, they charged an arm and a leg for that license. We are talking $600-800 for the license. Second, they would simply change to a higher version number whenever they wanted (usually annually) to push everyone to make another purchase. In other words, if BI offered this type of license they could go from v5 to v6 at any time and therefore not have to update v5 for people anymore. When companies to this annually, all they have done is charged people and arm and a leg for a version that is going to be obsolete in a year anyway. I've also dealt with companies that only offer a subscription license. This means that the moment you stop paying your monthly/annual subscription, the software ceases to function. It's a scam to get you hooked on their software so they can charge you for it forever and increase their fees at anytime too. The longer you use it, the harder it is to leave and change to another software and you can't stop paying or your software stops working.
BI is neither of these things and probably has the best/cheapest licensing (given BI scale and feature list) of any software that I have dealt with previously. I am not forced to pay for upgrades I don't want. Honestly I didn't pay for any updates for at least a year between the end of my initial 12 month support and the recent versions that allow substreams and AI. I looked at the new feature set and decided it was well worth the cost of a yearly support license to get these features so I happily paid my fee. Even better, the new 12 month support/upgrade time frame starts from the day you made the purchase. Most other companies will require to you "catchup" and pay for any time that you didn't have support/upgrades previously - but not BI. The fact that I hadn't paid for support for the previous 14 or so months didn't matter at all. I could have also just as easily continued to use my older version without paying any additional money.
In the end, the choice is yours to make - pay $25 for another 12 months of support/updates or not. But at least you can keep using what you already have forever. If you want to stay on the older version, simply roll back to the last update that was released prior to your initial 12 month support/update time frame running out.