Have Tier-1 visa but have not relocated to U.K. yet due to Covid

Hello folks
I have received my Tier-1 exceptional talent visa and have also collected my BRP in July. We live in the EU but are Australian citizens so we can come and go from the U.K. without impediment in normal non-Covid times.

However, due to the current Covid situation our move to the U.K. has been delayed. We aim to enter the country in May 2021.

Is it possible to get a delayed start of the visa once the BRP is issued?

What are the implications of not permanently moving to the U.K. for such a duration after the visa was granted? Does it make you ineligible the ILR or simply requires one to fulfill the requirement from the time we permanently enter the country?

I assume my NHS contribution for the year is lost - I paid for 5 years?

Anyone in a similar position that got clear answers from the Home office?

Is it possible to get a delayed start of the visa once the BRP is issued?

No.

What are the implications of not permanently moving to the U.K. for such a duration after the visa was granted?

It counts towards the 180 days absence limit in any 12 month rolling period, which would make you ineligible for ILR. You also risk having your endorsement withdrawn and this will result in the visa being curtailed/cancelled.

Does it make you ineligible the ILR or simply requires one to fulfill the requirement from the time we permanently enter the country?

Your visa route has absence limits. As you have presumably entered in your visa vignette to collect the brp, your clock has started ticking for residence

I assume my NHS contribution for the year is lost - I paid for 5 years?

It won't be refunded if you don't come to the UK under the terms of your visa.

Thank you for taking the time to answer specifically and clearly