Hi donato,
It is up to you to decide how the guidance applies to you, we cannot provide advice of this nature.
Working remotely for your Italian employer, while in the UK, counts towards the number of days spent working in the UK.
The personal allowance applies for the whole tax year even when there is part of the year, where you are not resident.
Please have a look at the table at:-
Residence, Domicile and Remittance Basis Manual RDRM12070 - Residence: The SRT: Split year treatment: Case1: Calculating whether individual works full-time overseas in the relevant period, to help you work out the number of days you can work in the UK and how many days you can spend in the UK.
If you are not resident for the whole tax year next year, you will not need to declare your Italian employment, as it will not be taxable in the UK.
Thank you.