I hope you are all great

My case:
- I changed from a Tier 4 to a Tier 2 on February 2015 so my sponsor was excempt of a Resident Labour Market Test (RLMT)
- My job was advertised in 18-22k, and I received 22k (the upper band)
- My SOC code salary range is New entrant: £20,800* / Experienced: £24,300
- My sponsor wants to raise my salary to 26-30k which is more than the SOC code salary (20-24.3k)band and also more than the salary job add (18-22k) for which I applied (although no RLMT was required due to the TIER 4)
-My responsibilities would not change in nature, I would just be having a raise of salary and maybe a change from researcher to lead researcher.
My question:
Do I need to apply for a new Tier 2 visa, considering the above? or can my sponsor just notify the authority? or nothing needs to be done?
I have researched online but I couldnt find information on what happens when there is a salary increase, but there was no RLMT to act as a reference point, and my job description would remain the same (researching) but from one level above.
Thank you very much for all the comments and help!
