[AT&T HTC One (M7)] HDClown:
I might be able to help you here. I went through all of this yesterday.

DISCLAIMER: IF YOU BREAK YOUR STUFF, IT'S NOT MY FAULT AND I PROBABLY WON'T BE ABLE TO HELP YOU FIX IT. DO ANY OF THIS AT YOUR OWN RISK AND DO YOUR OWN RESEARCH I still consider myself and Android newb (big time) as this is only my 3rd day into modding.

Go to this post: http://xdaforums.com/showthread.php?t=2365506

Halfway down the first post is the "Firmware Flashing" section where you can download all the bases. Note that 3.06.1700.10 is the GE base and 3.09.401.1 is an early leak of the 4.3 base expected with the 4.3 Sense release . All but the GE one are labelled custom although I don't know what's custom about them to be honest. Also there is a link to HBOOT 1.44, get that.

I flashed all of them in order, except the (GE one) like this: 2.17.401.1-> 2.24.401.1 -> 2.24.401.8 -> 3.09.401.1

Why did I skip the GE one? Solely because the .ZIP didn't say "custom". I have no idea what is custom on it. There really shouldn't be anythin gin that GE base that would do anything bad, and thus probably no reason to not flash that one before 3.09.401.1, but I didn't, so just telling you my experience as it occurred.

!!! This will upgrade HBOOT as you go if you use the files as-is !!! (As I recall, 2.24.401.1 went to HBOOT 1.44 and 3.09.401.1 to HBOOT 1.55)

Since you are S-OFF, you can just downgrade back to HBOOT 1.44. Or, to prevent the upgrade in the first place, you can extract each zip and replace the hboot_signedbyaa.img from within each .ZIP with the HBOOT 1.44 download. Then just re-zip the file and flash it. I ended up downgrading back to HBOOT 1.44 because you can S-OFF it if you need to set yourself S-ON again for some reason.

!!! Also important, this process made my touchpanel stop working on the JB 4.1.2 stock ROM !!!!! I believe this is because the touchpanel update included in 2.24.401.1 requires JB 4.2.2, which AT&T has not pushed out for the HTC One, but it is available on International models. So, if you have no intention to put on a custom ROM that is 4.2.2 (even the international one) or 4.3, then you need to remove the touchpanel update file (tp_SYN3202.img) from all of the firmware.zip before flashing.

If you already have a 4.2.2/4.3 ROM, then leave the touchpanel file in there.

If you are JB 4.1.2 and plan to immediately go to JB 4.2.2 or 4.3, then you can update the touchpanel even though it will make it not work in JB 4.1.2. Why? When you boot into custom recovery, the touchpanel itself will work (at least with TWRP 2.6.1.0, which is what I have running). I don't know if CWM Touch will work in this scenario, but you can use the physical keys for that one. But anyway, the point here is that you can update the touchpanel then immediately flash a new ROM and the touchpanel will work again. This saves you a step of having to update the touchpanel after the new ROM.

Something else to keep in mind is Radio's. The Radio's will upgrade with these bundles and you will end up with a radio different than AT&T's newest radio. My personal opinion is to stick with the newest AT&T release radio, which you can download here: http://xdaforums.com/showthread.php?t=2419699 - The one labelled AT&T latest is a flashable .ZIP you can load in custom recovery. Or you can extract the ZIP and copy radio.img over to your firmware bundles if you want it to just put in the latest radio with the rest of the firmware. You can also flash radio.img in fastboot with "fastboot flash radio radio.img".

Some people are saying the 3.09.401.1 is a little buggy. I'm not actually using my HTC One for anything but playing with ROM's right now. I'm using another phone as primary device still, so I can't provide any comments. You may want to stick with the 2.24.401.8 base which is the latest for 4.2.2 builds. That base will work fine with a 4.3 based ROM.

As for me, I currently have the 3.09.401.1 base but with the latest AT&T release radio and HBOOT 1.44 in place of what's in the original bundle download.