Hi,
Yes you apportion the income in relation to the start date shown on the declaration of trust.
You will not need to put any partnership income on your tax return if you received no income after that split in the relevant tax year.
However residential finance costs can be different. The interest costs are only allowable on the person who owns the mortgage.
This means that for your wife to claim any interest, the mortgage would need to be joint or in her name.
We have attached some general guidance:
Savings and Investment Manual
Factsheet: beneficial ownership
Partnership Tax Return Guide
Thankyou.