Many thanks for your patience, it is appreciated. I am now pleased to be able to provide further assistance with your query. First of all, I am sorry to hear about the issues brought up by this. It must be a frustrating situation to be going through.
The company would have only been obliged to tell you of the changes if they significantly impacted your ability to do the course. For example, if it was a one part course, which was then split into two parts, clearly they should have told you about it as that would have impacted how and when you do the separate parts and would have required some planning ahead by you.
If it was the other way around, where it went from two parts into one, what would matter is whether you could have still taken it in two parts, or the only way forward would have been to do it in one go. If the latter applied, you would argue that this was a significant enough change to prompt them to have told you about it.
Now that the deadline has passed, you can either ask them to extend that, or if they cannot do so – to refund you at least part of the fees. If they refuse, your only option would be to consider pursuing them for compensation.