Cancel standard application to switch to priority post is payment but prior to biometrics

Hi ,
I have applied for ilr using 5 year tier2 general (now skilled worker) route and with priority.
I also have applied for my dependents PBS extension for my daughter and husband with standard service.
Their current visa is valid till 7th JUNE 2021.

In case I plan to switch my husbands visa application to priority,(before 7th JUNE 2021)
1. Would I be able to cancel directly online from further actions tab in the application.
I could get link to an online form but that seems to be for a situation when I don't want to apply at all post cancellation.
https://eforms.homeoffice.gov.uk/outre ... 610878645
2. I understand from the gov.uk site that the ihs fee will be refunded. However would I get refund of visa application fees of around 14 hundred gbp as my husband and daughter have not attended biometrics.(scheduled on 11th June)?

I currently have both my daughter and husband in single application. I would be creating separate application in case I have to switch husband visa to priority due to a likely emergency situation at his home country forcing him to travel around 20 June.

Appreciate if anyone has got successful refund in the past in such situations.
I am not sure if the pbs dependent priority makes sense but just want to avoid 8 weeks of delays .


Thanks

Clarification - further actions tab does not have any options for cancelling online application.

Should i be creating a new application to replace this one?

Anyone who has done this recently can please help with the steps followed for succesful refund?

Thanks.

Anyone who has used withdrawal and got successful refund of application fees?
Any specific points to be aware of while using this form?