Conflict between CoS and Tier 4 visa.

[headset499]

I am a US citizen and a PhD student in the UK, but would like to play a week of UK gigs with my band which is based in the USA and whose members are all American citizens. I am the only one with a UK visa. The group requires a CoS (certificate of sponsorship) to travel to the UK for performances, paid or unpaid.

I am aware that the laws governing Tier 4 work activities prohibit being 'employed as an entertainer', as well as being self-employed, though full time work is permitted outside of term time (the gigs would be scheduled for July and August, 2019).

Does anyone have a sense of how risky it would be to attempt a music tour of the UK while on a Tier 4 visa?
Would my involvement in the CoS application increase or reduce this risk? Do certified sponsors even check visa and immigration records?

New to the forum, so please forgive any bad etiquette. Grateful for any advice.

[sah10406]

Does anyone have a sense of how risky it would be to attempt a music tour of the UK while on a Tier 4 visa?

Very. You cannot do that type of work under the Tier 4 visa conditions.

Would my involvement in the CoS application increase or reduce this risk?

It is not really relevant.

Do certified sponsors even check visa and immigration records?

Assume yes.

The only way you can do this lawfully is to return to the US to apply for the relevant work visa with the rest of the group,which would replace your Tier 4 visa. If it is a Tier 2 visa, you can then make a new Tier 4 application in the UK to complete your PhD, on the basis of paragraph 120A(a)(ii) of Appendix A of the immigration rules.

Whether you would need to formally interrupt your studies to undertake the sponsored work is a question for your Tier 4 sponsor.