Thanks for your reply.
I'm afraid that your friend could not sponsor you. It is only Employers who are intending on actually employing a tier 2 application who can apply for and obtain a licence to sponsor Tier 2 applicants. If you found an employer willing to do so then you could switch from your current sponsor to the new one without having to leave the country but you cannot do it with the involvement of your friend in the way you suggest.
I would approach the other council where you propose to work as social worker making them aware of your situation and asking whether they would be willing to apply to become a sponsor to enable you to switch. It's not that difficult and they may be interested if they are keen on your as a candidate. You may, for example, offer to pay their fees for this as an incentive.
You can switch in to a student visa category if you genuinely intend to study and have the requisite number of points, but I presume this is not attractive to you.
Let me know if any of the following apply and I shall further advise you:-
1. Are you in a relationship with a UK national, EEA member, person with indefinite leave to remain OR with leave to remain in another visa category
2. If you have any UK or commonwealth ancestry
3. If you have ancestry involving EEA member states.
If they do not apply then your only options are either staying with the council you are presently working with OR finding a new employer who is a licensed sponsor who is willing to employ you OR returning to Australia.
Sorry it could not be better news.
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