IOS 13 beta downgrade

Clearly you failed to read the Beta documentation in its entirety before joining:

https://beta.apple.com/sp/betaprogram/faq

What is the Apple Beta Software Program?

The Apple Beta Software Program lets users try out pre-release software. The feedback you provide on quality and usability helps us identify issues, fix them, and make Apple software even better. Please note that since the public beta software has not yet been commercially released by Apple, it may contain errors or inaccuracies and may not function as well as commercially released software. Be sure to back up your iPhone, iPad, or iPod Touch and your Mac using Time Machine before installing beta software. Since Apple TV purchases and data are stored in the cloud, there’s no need to back up your Apple TV. Install the beta software only on non-production devices that are not business critical. We strongly recommend installing on a secondary system or device, or on a secondary partition on your Mac.

Is the public beta software confidential?

Yes, the public beta software is Apple confidential information. Don’t install the public beta software on any systems you don't directly control or that you share with others. Don’t blog, post screen shots, tweet, or publicly post information about the public beta software, and don't discuss the public beta software with or demonstrate it to others who are not in the Apple Beta Software Program. If Apple has publicly disclosed technical information about the public beta software, it is no longer considered confidential.

Read our Terms for full details

No Support and Maintenance; Future Products.  During your participation in the Beta Program or in a particular seed, Apple is not obligated to provide you with any maintenance, technical or other support for the Pre-Release Software.  If, at Apple’s option, such support is provided, it will be provided in addition to your normal warranty coverage for your computer and/or device.  You agree to abide by any support rules and policies that Apple provides to you in order to receive such support.  You acknowledge that Apple has no express or implied obligation to announce or make available a commercial version of the Pre-Release Software to anyone in the future.  Should a commercial version be made available, it may have features or functionality that are different from those found in the Pre-Release Software licensed hereunder.

If you don't have a backup, then you will lose your data when you restore to iOS 12.

These are the steps to follow:--> How to uninstall iOS beta software - Apple Support

For any further question about beta software, contact Apple Beta Software Program, since we (you included) can not discuss about beta software in this public forum.

Giulio

No, there is no other way to downgrade and save your data. That's why the instructions specifically tell you to make a back up first.

Landhoff wrote:

I signed up for "public beta" in a very public and official way from an open Apple site. So why don't you think I (we) can discuss beta software openly?

I mean it's not like I'm asking "dudgy" questions or anything...?!?\

Because that is Apple's rule. You agreed to Apple's Non-disclosure Agreement when you signed up for the beta program. It explained all of this.

Landhoff wrote:

I know, I was on summer holiday unable to do the necessary backup. So, I took the chance not realizing that so many apps no longer works after beta install.

As Apple says in the section that Phil posted, you shouldn't be putting beta software on your everyday device. It's just a bad idea. Beta software, by definition, is full of bugs.

I'm sure it does. But who reads all these NDAs, T&Cs etc. etc. I mean they are massive - especially for US companies. If you want to go through all that stuff, not the least to fully understand the often very "legal-isch" language used, you will never sign up for anything, certainly not spontaneously.

I read them.

And it is a legal, binding agreement. Violation of the NDA could result in the violator being sued. Intellectual property rights are a big thing right now. If I was going to read and understand any of these leaglease documents we are presented with when signing into something, an NDA from a company would be the highest of priorities.

ChrisJ4203 wrote:

And it is a legal, binding agreement. Violation of the NDA could result in the violator being sued. Intellectual property rights are a big thing right now. If I was going to read and understand any of these leaglease documents we are presented with when signing into something, an NDA from a company would be the highest of priorities.

Very true.

If more people read those they wouldn't make spontaneous decisions to put test software on their iPhone while they are on holiday.

You could turn on iCloud Photo, which works on all versions and move your photos to iCloud and then recover them after you roll back.

We cannot discuss any aspect of the beta program in this forum even though there is a public beta operating system. Those are Apple’s rules.

Landhoff wrote:

No I did not fail to read it - I deliberately chose not to!

Then you have no one to blame but yourself for the loss of data you'll suffer when you revert to the shipping release.

IdrisSeabright wrote:

I read them.

Me too.

Also, the Beta FAQ is not very long.