I went ahead and switched to the SAVE plan. You can actually go through the application process and near the end of it, they’ll provide you a list of plan options and how much you’ll have to pay, if any. If you would have to start paying, you can quit the application and no changes will be made to your current plan / certification and at least you won’t get “sticker shock” down the road and can start planning.
If you’re using Android, check out xmanager. It’s basically a free cracked version of Spotify Premium.