Excellent, mate!
Yes, so the Program Change (PC) events has the range 0-127, so effectively 128 programs can be used.
But, after the fact companies started to add a few Continuous Controller that essentially amounts to “Bank” messages. Unfortunately these aren’t as straight forward as PC. The reason is basically because banks were never part of the original MIDI specification, so the companies implemented them differently and this is what we now are stuck with. 
However, it works, and thanks to companies like Steinberg (and others of course) it became fairly straight forward to set the application up to accommodate the lack of standard. The MIDI Device Manager can help with the inconsistencies and present a better solution for us the users. The bummer is to have to set this up, if a device does not already exist, and this can be tough if you are just beginning. 
Anyway, so in essence the PC means Program Change within-the-currently-selected-bank. So if the device can respond to bank messages, then you can send a bank change message and then send an additional PC event, and you can access the entire range of patches within a device. 
What hardware devices do you have, if I may ask?
Myself I have a slur of stuff that kept from younger years. Just cannot see a reason to actually get rid of them anymore. 
I used to have loads more, but when I moved to the states, I just needed to rationalize. Well, I use that as an excuse in order to not feel bad about giving away a lot of treasures.
I have two antiques, which are also the most valued among the lot. JLCooper devices, but they aren’t sound devices, they are MIDI routers. Meaning, that they can (re)route MIDI events based on the settings on the front controls. One is programmable and is useful for a large setup of various devices, whereas the other one is more for usage of many keyboards. I also use a Midex8 since many years and it has diminished the use of the Coopers, but they are still needed.