Again, your approval date isn’t relevant. Only your Priority Date (i.e. the date you applied) is. So Table B is just for submitting your docs etc, there won’t be a visa available until it’s current on Table A. So that’s currently 1st July 2010, 2.5 years before your Priority Date.
But it’s not linear, so you can’t assume it will be another 2.5 years until your Priority Date is current. If you go back and look at previous Visa Bulletins, you’ll see that it usually moves much more slowly. For example, if you go back 5 years and look at March 2020’s Visa Bulletin, you’ll see that the date on that was December 2007, so in 5 years it’s only progressed by 2.5 years. That’s why I said my guess would be another few years.
The embassy in the UK doesn’t have anything to do with it yet, not until your case is being sent for interview. But no need to update anything now, when you do fill in the DS-260 you’ll update the address then. Everything is sent via email, not post.
And I think @Boiler is referring to healthcare costs for retirees.
Best of luck.