There is a shortage of teachers and a real concern with recruitment (everywhere).
Retrenchment is unlikely to hit the education industry, but your friend should look at job fit more than just "risk of retrenchment" to determine what is a good career for herself.

What is the average merit increment for GEO5 and SEO 1 ?

I thought the Ministry is saying that there's excess everywhere, and numbers can still fall further?

Do any of you feel guilty when you leave the office on time? With the work completed, what's the point of staying back just to appear busy? I was casually asked by a colleague about my early departure, who jokingly suggested if I had another job on the side, based on what she claimed she heard from someone. When I asked if she stays back in the evenings despite having no work left, she said yes. It made me ponder the culture of presenteeism in our workplace and whether it truly adds value.

The numbers have to fall further to meet the manpower planning targets that are determined at the whole-of-gov level. However this does not reflect the real staffing needs on the ground.

Those people who wanna climb and get promoted to KP always stay back until 5.30 or 6pm. I used to go home at around 2plus pm and I am sure the KPs criticised me for leaving early (behind my back)

It depends
 

It really depends on the school culture and your KPs. When I was a young officer, I will go home if I have nothing on and when I became a KP and RO, I always emphasized to my reportees to go home if there is nothing on for them. Staying late in school just for the sake of it is a concept that I am not able to comprehend. I will only stay if I absolutely have to as I have a life outside of school.

Now as a HQ officer, usually we will still knock off on time but there is always exception as sometimes we have to rush out work and clear things with our bosses.

I feel guilty for 3 secs on those days I leave early, but than i quickly thought about the other many late days I had to pull through to get work done and that guilt is released immediately. :)

As an advice, I think you don't need to compare yourself to others. Be confident of your work contributions. I think a lot of such guilt sometimes comes from your fear that you are not seen as "performing" as well as others due to work hours. But people have different reasons for staying in school, and our schedules are always diff from 1 teacher to another due to diff duties. Some even choose to stay in school a bit more to avoid home a bit.

But if you regularly have a lot of days where you can leave early, and colleagues have that impression of you being employed "outside", than the bigger issue may not be your work ability, but whether you have been meaningfully deployed to contribute.

Life is short. Don't stay back and end up looking like a clown. In reality, no one really cares.

Honestly nobody cares, we start at 5ish am - 7am already reach school, on the good and happy days we leave at 2pm (including KPs)

On the rough days (CCA days two times a week) we leave at 7pm
Got lesson late also end near 4pm

Nothing to feel guilty about that one day walking away at 2pm