Confused about allowed length of stay

[anthonyb123]

My wife is currently in the UK on a visitor visa, I have some questions regarding how long she can stay in the UK for.
The current visa details are:
Type of Visa: C
Number of entries: MULT
Duration of stay: 180
Remarks: C-Visit

When we initially applied for the visa we put on the application form that my wife was planning on staying for 23 days. Then we were granted the multiple entry visa with a 6 month stay, so we decided to change our plans for her to stay for around 3 months.
When my wife got to the UK border, she was briefly detained at the border subject to further examination by an immigration officer. After my wife answered some questions, and I answered some questions by phone, she was allowed to enter the UK. The immigration officer said that she recommended my wife only stayed for 23 days.
We are now confused as to how long my wife can stay in the UK for, (1) can she still stay for up to 6 months like her visa says or will it count as overstaying if she stays for longer than 23 days?
(2) If she can stay for longer than 23 days, would doing so have any impact on subsequent entries on this visa?

Also, we are planning on applying for a ‘Family of a Settled Person Visa’ in about 6 months time and had a few questions regarding this.
(3) Will staying for longer than 23 days have any impact on our application for this visa
(4) Is there a minimum amount of time my wife must have been outside of the UK for before she can apply for this visa

[Casa]

My wife is currently in the UK on a visitor visa, I have some questions regarding how long she can stay in the UK for.
The current visa details are:
Type of Visa: C
Number of entries: MULT
Duration of stay: 180
Remarks: C-Visit

When we initially applied for the visa we put on the application form that my wife was planning on staying for 23 days. Then we were granted the multiple entry visa with a 6 month stay, so we decided to change our plans for her to stay for around 3 months.
When my wife got to the UK border, she was briefly detained at the border subject to further examination by an immigration officer. After my wife answered some questions, and I answered some questions by phone, she was allowed to enter the UK. The immigration officer said that she recommended my wife only stayed for 23 days.
We are now confused as to how long my wife can stay in the UK for, (1) can she still stay for up to 6 months like her visa says or will it count as overstaying if she stays for longer than 23 days?
(2) If she can stay for longer than 23 days, would doing so have any impact on subsequent entries on this visa? Future visitor visa applications may come under scrutiny if she stays longer than the original stated 23 days. The ECO may doubt her true intentions on the length of stay when she re-applies.

Also, we are planning on applying for a ‘Family of a Settled Person Visa’ in about 6 months time and had a few questions regarding this.
(3) Will staying for longer than 23 days have any impact on our application for this visa No
(4) Is there a minimum amount of time my wife must have been outside of the UK for before she can apply for this visa No

[anthonyb123]

So to clarify, you are saying that she can stay for up to six months but if she does then it might have a bad effect on future visitor visa applications. But it won't have any effect on the Family of a sealed person visa because that is not a visitor visa?

[Casa]

Exactly.