Hi there info-bmfequipeme,
It's awesome that you're exploring to different QuickBooks Online plans to get the features to best help you with your business needs. I can point you towards the right direction to get your subscription level modified.
There are two ways of purchasing your QuickBooks Online account, one being directly from intuit and the other through the app store on your Apple or Android mobile device. Since you created your subscription on your iPhone, your billing is being processed through the Apple Store, and it's normal that you don't see the option to switch plans while logging into the browser. In order to upgrade or downgrade your subscription for an account created in the app store, you can contact our support team outside of the community site so they can verify your account information securely. They can then help change your billing from our partner to Intuit in order to be able to change the subscription plan. You can get in touch with them by one of these methods:
Phone: Call us at 1-855-253-1536 from Monday to Friday between the hours of 9 AM and 8 PM EST.
Schedule a Callback or start a Chat: click (?)Help in the upper right > type and enter "Contact support" into the QB Assistant > click Contact Us > explain your situation > click Let's Talk > choose Get a callback or Start a Chat.
Social Media: Facebook, Twitter, and Instagram.
Let me know how it goes and if you have any more questions. I've got your back!