With regards to residency and ties. 23 days is wrong. Google the SRT
Statuary Residency Test
Case 1
Less than 40 days - non resident
Case 2 More than 180 days - resident
Case 3 In between. Allowable days dependent on ties.
Family tie
Accommodation tie
Employment tie
More than 90 days in the previous year - 90 day tie
Total number of ties determine how many days you can spend in the UK before being considered a tax resident. Be careful on the definition of a day.
Be particularly careful WRT capital gains tax. Non res. no capital gains on off shore assets.
UK res. Capital gains applied to worldwide assets.
Also look in to Split Year Tax rules. If you sell up before you repatriate you may be considered non res before the date you repatriate.
It's all there in black and white on HMRC web site. A big step forward from a rather arbitrary decision by HMRC on the concept of domicile.
But if your thinking of going home the capital gains tax is the big one. Don't get that wrong.