constructive dismissal@early termination? salary deduction

Greetings. I worked at a manufacturing company in Nilai for 3years +. During those years, i was in production control / warehouse dept. , and production dept.

1. does the employer/AGM has the right to transfer an employee to another department without notice or official letter? and it's via verbally too. The day i was informed was the same day i transferred to another dept. No appointed letter, and nothing mentioned from my offer letter regarding transferring dept or whatsoever.

2.  Working hour 8am-6pm. but only for the front office staff (I'm one of them), AGM instructed  for us to punch-in 0750am the latest, and out by 610pm the earliest because she wanted to show to other employees how 'discipline' the office staff are. I was particular about my personal timing, and i consider up until 0759am would be my personal time. Plus, having to allocate 20 minutes everyday with no pay just to show off to other employees was a bit of a stretch. I do comply at first, but 3 years in, i would be off by few minutes, still not exceeding 8am. and of course, my AGM was not happy about it, so, she issued a 'memo' saying if i was late than 0750, i would not be allowed to park my car inside the provided parking space. and that's applicable to me and me only. i know this is just small matter, and it's not that i really care about the parking space, but can employer impose action just for one employee? Was i in wrong in this matter? I'm not sure that i am, since

a.  it does not break any company policy because it actually starts at 8am,
b. 90% employees punch-in after 0750,
c. there are other employees that punch-in after 8am, but didn't even get any sort of action. no warning letter, nor showcause letter (not that i want my fellow colleague to be punished)

- the AGM do aware of b. and c.
- i once asked HR the handbook about company's policy, but she said that we don't have one (the book)

3. Not long after the parking memo incident, AGM then transferred me to production department because it has been said that she 'could not bear' to look at my face in the office anymore. This department was managed by 1 x manager, 1 x jr executive (me), and 2 x supervisor (SV). Other than our own job scopes, We oversee over 60 technicians and operators under our  dept, and do all the filings (we don't have clerk). Everyone helped each other out and it was great.

Here's the problem lies. There was a period where my manager on medical leave for 10 weeks, and both SVs resigned few weeks before that. so basically i have to do 4 persons' job during all those weeks, plus having to train the replacement SV who would change constantly every 2 weeks (they resigned). With all of that going on, I would be experiencing burnout once every one or two weeks.

On top of that, when i just remembered that our increment had started couple of months before, i read and checked my increment letter and i realised that i got 0% increment. Because of that, plus my manager informed that his leave got extended for a few weeks longer, and still having no replacement for SV, i sent in a month notice accordingly to my offer letter. I have been told that AGM was happy about it (shocker) and one week after submitting, HR called me in and inform that my resignation has been accepted and effective immediately, which means that day was my last day instead of 3 weeks later.

⁃ is that allowed? Is there any law regarding my situation? i never got warning letter, show cause letter, nor DI.
⁃  Considering that i was dismissed earlier than my official notice, should/would my pay going to be calculated until the earlier date, or my supposedly resigned notice date?

*i have been researching on Employment Act 1955, but apparently that act is only applicable for employee that earns below RM2,000.00 monthly.

A resignation letter has been submitted, why discuss on constructive dismissal??

EA 1955 does not speak on matters after a letter has been voluntary submitted.

The day my doter submitted her letter, within 2 working days, the company send a courier service to retrieve company hp, note book, docs.. etc etc.. and was already deleted from the company's servers

There is no laws pertaining such matters after a letter of resignation have been received.

I see.. i mean before resigning, when the employer purposely singling out punishment to one specific employee, or transferring an employee to another department with different job scope, without notice or official letter (via verbally), is that considered as constructive dismissal? And also informing the resignation take effect 3 weeks earlier than the notice given by the employee without cause. Is that equivalent to getting fired, or what? 

transferring an employee to another department with different job scope

My personal view :
 A disgruntled employee should then resign after that month's pay and the file for constructive dismissal at the IR Dept seeking reinstatement or arbitration.

After working for a few months then the labour Court will deem that you have accepted the transfer (whether written or verbal also applies).

And also informing the resignation take effect 3 weeks earlier
I have stated above, once the resignation letter has been tendered, the employer can ask the employee to leave the company premises immediately to avoid loss of company's data and  /or sabotage activities. The employee is still deemed working for the company until the end of the resignated period unless in written consent. However the company must pay until the "last day of employment" whether or not you are inside the company's premises. This is industrial practice, not inside employment laws.

To file for reinstatement in IR Court /Dept, one must make an application within 2 months from "last day of work" with the company.

In actual fact, the moment a resignation letter is tendered, the company can bar the employee within the same day..!! (but must pay).