u/Downtown-Scale-6155

I have been running a business as a sole trader for a few years and after doing a fair bit of research over the last couple of months, I have decided to change to a partnership with my wife. She is going to register as a sole trader for SA and then register the partnership.

Despite reading mountains of info on gov.uk and other sources, I can't find the answer to a couple of questions I have and I'm hoping someone here may be able to advise. (I will obviously contact HMRC when they re-open after the Bank Holiday though!)

1. How do I change the details in my business tax account on the HMRC website to reflect the change to a partnership? (We will be starting it from tomorrow for the start of the 2026/27 tax year.)
2. I am registered for MTD for IT for 2026/27 due to having qualifying income over £50k in the 2024/25 tax year. Will I still need to do that as my sole trader share of the partnership income of 2026/27 will be half of previous years' income? If so, how do I input the values for income and expenses into the MTD system?