Should i be an 'I','T' or a 'M' type of Product Manager?

I am a Product Manager with Walmart's ASDA Ecommerce Business. I made my transition from a Program Manager role to this role about a year back. My excitement to learn and do more in this role only shoots up everyday. Here is an interesting peek into my everyday thought i want to provide to my readers.

Being in my last role of Program Manager, it was a normal thing to work on programs that include the solution/product/feature my team was shipping but and also interact with so many teams that were either dependent on our work or vice versa. For instance, while being with a team where we were developing and shipping solutions on Personalisation, there were innumerable times i was driving programs which involved Check-out, Browse, Order Management, Payments, Cart, Search, Content Management or even infrastructure.

And yes, i was listening to everything that was being discussed in those meetings, googling, finding videos on what term or concept i felt i did not know but was curious to.Have you ever had a moment like this on a call where someone said we are waiting on the SDKs and you start typing the term on google to search what that means? I am all that :)

Now being the Product Manager of one of such specialised domain, my biggest mission is to determine what should i do with the lateral knowledge i acquired in my previous role.

Its quintessential decision to make sometimes, when you are in a domain specific role, on if one should continue to sharpen the same axe only in that domain or gather more weapons in your arsenal that give edge on knowing a full picture. Basically yeah! i am talking about should you structure your knowledge in a 'T' a 'Comb' or just an 'I' shape.

Its purely dependent on how curious one is and how big a picture they are willing to se while still building expertise in their domain.

After a deep rumination, i concluded that i would want to have my knowledge to shape like a 'T' while at the outset of my role and develop a 'M' or a 'Comb' as i go along learning more.

What is the shape of your knowledge?