switching from tier2 ICT long term to Tier 2 general

Dear Manci

I need your urgent help please as am in a peculiar situation

I first came to UK in june 2009 on a "VISA WORK PERMIT" valid from 1st may 2009 to 1st may 2011 via my employer A , i stayed for about 4 months and returned to india in late 2009. That visa ofcourse expired in 2011 but i kept on coming to UK on business visa thereafter many times.

i remained with same employer (i am a continuous employee since 2006) who sponsored my TIER 2 ICT LONG TERM STAFF MIGRANT visa in may 2013 and came here in november 2013. I also moved my family with me. Last year when the first two years were coming a close, i applied for the extension and mine and family visa was extended till May 2018.

Now i wish to transfer to TIER 2 General visa. my questions are as follows:

1. If I stay with the same employer, can i apply for a switch to T2 General while remaining in UK ( since i had earlier stayed in UK (prior to 2010) on a Visa work permit for same employer - not sure if that will be considered in any way - or was that done and dusted)

2. If my salary crosses the 1,55,300 mark with the same employer , can i apply for a T2 general visa while staying in UK

3. If i wish to move to a different employer (say B) , who is giving me more than 155300 (including bonus/allowances) then would they need to file a fresh CoS/ Visa application and the the cooling off period wont apply ?

4. In case of 3 above, if no cool off is required would I be required to file the visa from india or can i do that while being in UK on Tier 2 ICT for employer A.

I would be really obliged by a response. PLease do advise sir.