The first stages were fairly straightforward (Situational Judgement test, application form and video interview). I used glassdoor to find potential questions before the video interview, and it helped a lot, there were no questions that I wasn't expecting. Also, you get to see the question before you begin recording for 30 seconds, so I would recommend having a pen + paper to stick some bullet points down in this time in case you get stuck. Additionally, I stuck some notes around my webcam/in the background to glance at if required. The hardest thing was talking without having to rush or waffle, as you are allocated different amounts of time to answer each question.
At the assessment centre, there were 4 candidates (including myself). I believe there should have been 6 of us, but 2 people didn't show. There were 2 assessors (one nice and welcoming, the other not so much) who introduced themselves and then asked us each to introduce ourselves and tell the group our favourite ALDI product and why. We were then asked to pick a number between 1 and 6, to decide the topic of our store walk presentation (I assume all the assessment centres they run will have 6 candidates so there is one topic each and nobody has to present the same topic). I had prepared notes on all of the topics and you are allowed to take your notes in with you - I found all of the topics on glassdoor: Store Layout, staff behaviour, till systems, specialbuys, product range (excluding specialbuys), and customer behaviour. I thought that my presentation went the best of the 4.
In the afternoon, we were all given 10 minutes to read through a booklet containing a job description and 4 applications. We then had one minute to present who we had chosen to the group and why. Following this, as a group we had 20 minutes to decide on which candidate we would select and why, to then present back to the assessors. Half way through this, we were given another application to consider. The hardest part for me personally was reading through the booklet in 10 minutes. There is a lot of information to take in, and I didn't manage to even finish reading, putting me at a big disadvantage. The other candidates therefore dominated the discussion. After presenting our choice back to the assessors they fired back some tricky questions, which were clearly already written down so no matter who we chose they would put pressure on us and see how we reacted. I would strongly advise to practice reading through a bunch of CV's and learning to pick out the relevant information quickly. It seems that ALDI haven't changed their assessment centres for a couple of years, with even the names in the booklet being the same as some older reviews on here.
I got an email just over a week after saying that I would not be advancing to the final interview. They also gave no feedback - very frustrating considering I had to travel a long way, stay in a hotel, and the fact that I spent a long time preparing and the process itself took 3 months.