Hi,
We would suggest that it would be your personal choice whether you updated your bank details as it is something that HMRC would not be concerned with.
2, Unfortunately we have not been given the example of the format you suggested.
Please refer to the following link in respect of the Declaration of Trust:
Trusts, Settlements and Estates Manual
3, Your wife would have to declare her share of the Income from Property in question from the date of the Declaration of Trust.
Thank you.