Good luck on your training!
Personally I would leave the HIAB/ADR training until you have got some miles behind you, having them will for sure make getting work easier, but until you have some experience, getting that first job can be difficult, and even fewer places will hire for transporting dangerous goods or letting you loose with a HIAB, and its a lot to learn trying to go for too much in one go training or work could end up costing you.
On the theory’s side of things, Pete makes some very good points, for reference up in Aberdeen myself, and I booked mine in just as we where allowed to again, towards the end of July, and first proper date I could get the theory and hazard perception booked in was a 6 week wait, there where odd slots where I could do one but not both it was also in Fort William a 415mile round trip 
(would have been shorter but the mountain roads made SWMBO feel ill so went the long way back down to Glasgow and back up) Wasn’t able to book Mod 2 in at the same time, and around work was not until October in Glasgow a date was available but again it was slim pickings and that was across the whole of Scotland and another 300ish mile round trip
I could have done it more locally but to fit in around work and reasonable times It was spread out more time wise, but still even if just picked the first 3 that where available would have spread it probably as far north as Wick and down to the borders for each slot, difficult to get one after the other so could well have be 3 trips. Assume less mileage down that way to do things but travel IMO will be a must if want them done if a short timeframe.
On the auto/manual side of things, personally I would say do the manual on the car, then Automatic on truck I am training at Pete, well 2 days in and get to finish it when Boris lets me! Class 2 and while the little 12 ton DAF Automatic is a perfect training vehicle, fits the rules, no massive scary tailswing etc to worry about, and probably as nippy and nimble as you are going to get in a truck heck it doesn’t feel that big at all, It really is a lot longer, wider, heavier and slower than a car and its a truck so everybody and their gran wants to get in front of it add the L plates to that as well, so getting used to the extra size, turning circle and having to battle with car drivers shoving past you adding in getting used to gears as well, is just an extra thing to worry about and one you don’t have to, and while yes you do sometimes have to wait for the gearbox to make its mind up, once you work with it rather than fight it, the extra little bit of “control” from a clutch pedal is not missed.
I fully sympathise with your desire todo it as quick as you can, so do I and the waiting from sending off my forms to the 8 hour trip down to Pete, was a lot of stress, anxiety and worry, and it was gutting that had to stop on day 2 (Thanks Boris) and go home, but still very glad didn’t force todo everything to fast, still more than glad I chose to go down to Pete over a local school even though testing still allowed up here, since when I next make the trip down I know I had time to do everything well so far, the training and atmosphere is top notch, I won’t lie my heart was going like the clappers walking into the tests centres for my theory’s, but for everything practical wise I was perfectly relaxed,(KALMS helped with this as well) made the whole thing very easy to get on with, I know will get looked after so not really stressed anymore and looking forwards to passing the test, getting work doesn’t seem all that scary anymore.
You have picked a good school which is must in the help you will get before you go, get the KALMS on the go as well, make sure you are relaxed and unstressed as you can for that getting up on the that air suspended seat (awesome things by the way) for the first time, the wait is and will be worth it.
Bit of a ramble sorry but hopefully it helps
I immediately went online and booked my theory and hazard test both in one day at the same centre .
Happy days