Tier2 General LtR Extension Refusal-Reapply Advice

Hello,
Firstly, thank you in advance for you time and your advice is much appreciated!!!

My application was refused last week due to the salary fail to meet the target but my employer has agreed to help me meet the target and provide me a New COS for a new application.
My question is can I start a new application as soon as I received the new COS? is there any time frame issue I should be aware of (something like the cooling period)? The case officer (I applied in person) only mentioned that I should re-apply two weeks before my current permit expired, which is not a problem in my case.

Also, although the case officer said the refusal won't bring anything against me, I am still concerned about it. Is there anything I should know for my new application? or should I just treat it as a "NEW" one? Sorry for being so vague but the extension application process is (supposed to be) quite straight forward and there is not much information to consider...

Thank you!

You can apply whenever you wish to. No such 'cooling off' period.

Refusal should have no effect on your next application.

CR001 wrote:You can apply whenever you wish to. No such 'cooling off' period.

Refusal should have no effect on your next application.

Thank you so much for you reply.
I have another question if you don't mind give me some advice please.
The case officer told me she will arrange a refund of my Health Surcharge along with the refusal but I haven't received anything (not even a notification email) yet. Shall I use the same payment reference number for my next application or shall I pay again to get a new reference number for Health Surcharge just in case?
Many thanks again.

IHS refunds can take a while.

You will have to pay again and get a new IHS reference number.

Thank you so much!