Sometimes you just have to be aware of what's out there. The company can't text everyone (over 1 million people) every time the plans change. A quick look at the website would tell you what's available.
I think the $45 plan offers better value than what you have now. For the extra $5, you'll get 500 minutes instead of 150 and double data too. Everything else is the same, including evenings/weekends time. It's probably better than continuing to pay the overage rates on your current plan.
As someone new to data plans is there any site to estimate data amounts based on your type of usage? I will be tethered to WiFi at home or office for upgrades and media us and mainly focused on email and social media when not on WiFi.