Hi,
I think your answer is correct.
1) Is this the first time you have applied for a partner route, or an extension, with your current partner
(including as a fiancé(e) or proposed civil partner).
This is how is read the question.
1) Is this the first time you have applied for a an extension, with your current partner
(including as a fiancé(e) or proposed civil partner)
YES
I was also stuck with this question but in previous post someone has answered this.
Reason for extension
Please choose the reason you are applying for an extension, this includes if you are switching to a partner visa from another type. (Required)
First extension as a partner (following an initial period of entry as a partner, or as a fiancé(e) or proposed civil partner of a settled person)
Additional extension as a partner
First application as a partner from within the UK (for example, you are currently in the UK on another type of visa or permission to stay)
You delayed your travel to the UK by more than 3 months after the issue of a visa and have not yet completed the required amount of time on a partner visa (not including as a fiancé(e) or proposed civil partner)
You require more time to meet the Knowledge of Language and Life in the UK requirements to apply for settlement
You were granted entry as a fiancé(e) or proposed civil partner, but have not yet married or entered into a civil partnership
You are applying for any other reason