iOS Question iOS-App Deployment

Hi there,
I've read some topics on this forum regarding the iOS Deployment pipeline and I have some question about.

My goal is to upload an iOS-App somewhere (own server ? B4i Server ? iTunes ? Diawi ? ) and let the users install it.

Do I understand right, that I need a provision file with all the UDIDs of the devices on where the App will be installed ? This is for me - and my customer - a no go, since we don't have any clue about the UDID of all the devices of the occasional customers. More, the installation process will be rather complex, because each customer should first send us the UDID of the device, then I should generate a new provision file with his UDID, and finally upload a new build with the new provision file. And this is required for all the users that want to install the App.

I've understand that the need of the UDIDs is no longer required when using an Apple Developer Enterprise Program (299 € / year) and In-House builds. Is this assumption right ?
Source:

if you are using a Development or Ad-hoc provisioning profile, devices' UDIDs must be added to the provisioning profile used to sign your app. In-house builds with an Enterprise Apple account don't require registering UDIDs

Click to expand...

I wonder if I can achieve the same with my current normal Developer License (99 € / year) that I've enrolled, if I upload the iOS App on iTunes. Am I right ?

Since I've not yet deployed any App on iTunes, I need badly some clarification in order to follow the right path for my customer and for me as developer.

Any help will be greately appreciated. Thanks in advance.
Sergio