Currently offered an AM post in a Stat board.

Was a temp staff (Senior Executive) for about a year and successfully got an Assistant Manager level post. I was also informed that I will be under MX12 with about 3.7-3.8k.

However, HR told me that my prior experience although relevant will not be considered as it is under casual experience.

Total work experience under 1 year and got second upper class honours for my degree.

Can I check if this is the norm?