Transfer from Tier 2 dependent to Tier 2 main applicant within UK

[Sri12lucky]

Hello,
I am currently on Tier-2 visa which is valid until Aug'20, on which, my wife and son are dependents. In next few months, my wife's organisation is willing to sponsor her Tier-2, on which me and my son will be dependents. I have few questions around this circumstance.

I understand that my wife should drop Tier 2 visa from her (our) home country, Can we both drop the visas (she-main applicant and me-dependent) at the same time?

Follow up question: If the answer to the above question is NO, which means, she has to drop her visa at her home country; come back to UK and then I (and my son) drop the dependent visa on her here. Is this correct?

My second question is in regards maintenance of funds. Can I show my father's bank statement/ funds (he can also provide a covering letter) which are there for 90 days in his account back home.

Say, I switched to dependent visa in May'20, does it mean that my son's visa (which is valid until Aug'20) will cut short to May'20 (i.e. will my son's visa expire on the day I switch my visa-as he is my dependent currently)

Sorry to post many questions.
Regards,
Sri.

[CR001]

You can all apply outside the UK if you are all outside the UK. If only your spouse is applying form home country, you and your son can apply in the UK once your spouse returns with tier 2 visa.

You cannot use your father's bank account for maintenance funds. It must be in either your or your spouse name for maintenance proof.

Your son must also apply for a dependent visa when you do. His visa is wholly dependent on your current visa status and you should both apply at the same time to switch visas.

[Sri12lucky]

Many thanks for the prompt reply. I have another follow up question. After our family dropping the visa in our home country (my wife as Tier 2 main applicant and me as her dependent), do I have to return to UK alongside main applicant or can I return first followed by main applicant.
Regards,
Sri.

[Sri12lucky]

Hello,
I am currently working for a company for last two years on Tier 2 dependent visa. My company is now willing to sponsor me Tier 2. The question is what start date do they have to put on my COS. As per UKBA processing times it takes 15-20 working days and can I put a day after this time period as starting date?
Thanks and regards.

[Sri12lucky]

Hello,
This is my current situation.

Visa Status: Tier 2 General-Dependent
Visa Expiry Date: 14th Aug, 2020
My situation: As of today, Covid-19 cases are rapidly raising in India and there are no flights running (except in emergency ones) and I am three months pregnant.

I am currently working for an organisation which provided me CoS last month and I am planning to switch to Tier 2 General (as per new Covid-19 UKBA guidelines, this switch can happen within UK). However, UKBA website suggests only the categories shown below can switch within UK.

Tier 1 visa, Tier 2 (Sportsperson) visa, Tier 2 (Minister of religion) visa, Tier 2 (Intra company Transfer)
Tier 4 visa - if you have an eligible qualification, will complete your course in 3 months, or you’ve done at least 12 months of a PhD, Start-up visa, Innovator visa, a dependent partner of someone with a Tier 4 visa or
a representative of an overseas business.

How do I go about this? Can I apply under switch within UK and attach a cover letter stating my reasons to apply within UK?
Many thanks in advance.