Work Permit to HSMP, while in UK

[Sher]

1.]
Were I to first land in the UK as a 'work permit' holder, am I right in understanding that I can move to the 'HSMP' programme while being in UK ?
If so, there may come a point in time where I hold both a work permit and an HSMP approval. Is that okay ?

2.]
Do I have to inform my employer about the move to HSMP ?
(My employer might not like it 'cos of the ability to switch jobs)
Is there a way one can make a smooth transition from the work permit to HSMP programme without bringing the employer into the picture ?

Thx.

[try-one]

Hi.
1- You can apply to HSMP from anywere in the world, including UK.
2- You apply for the HSMP personally, your employer would NOT know. Once you get the HSMP approval, then you need to apply for FLR (Further Leave to Remain), once they give you the FLR under the HSMP then the WP visa becomes invalid, the HSMP overrides the WP as I understand.