28 days grace period application from PSW to Tier 2(General)

[Lokez21]

Hello,
Hope all is well with you guys. I am looking for some guidance regarding my case.
I am currently under PSW visa and I am waiting for the sponsor's license to be awarded for the company that I work for. The company has been carried out with the company checks by a compliance officer, last week. The company is expected to be awarded a sponsor licence(assuming).
Now I am under 28 day grace period and my visa expired on April 13th. I was expecting to submit my application along with COS during my grace period but unfortunately there is a delay in processing our company sponsorship license.

My Questions are:
1. Can I still make an application under Tier 2(General) stating that 'the company is currently awaiting a decision on the sponsor licence application'?
2. If yes, what are all the documents I need to provide them as a temporary replacement for COS.
3. My employer has to terminate my employment legally. Can he still assign the unrestricted COS as I am already in the UK and I worked for him for almost an year as a software developer?
4. His business will seriously hamper as the role I do is much advanced coding which cannot be easily replaced. Do I have to mention it anywhere in my application provided the statement is signed by the company itself. Or do the company have to mention this with their sponsor application?
5. Will my company have to do resident labour market test if my PSW visa expired Or I get to keep this privilege during 28 days?

Thank you
Lokesh