Rearranging PIP home assessment

My appointment letter for PIP has come through, I'm having a home assessment with Capita (which I didn't actually ask for so I presume that's a good start). My partner isn't able to be at the assessment with me because of work so I'm considering asking to rearrange but I've got a couple of questions first.

1. Do you get any say in the date or is it just luck? The only date in the next few months I absolutely cannot do is 15th April because I'm getting married, will they take that into account if I tell them?

2. Do Capita do assessments on weekends or bank holidays? Our wedding is Easter Saturday so bookended by bank holidays.

3. How long is it likely to take for a new appointment to come through? It took just under 2 months from them getting my form to giving me this appointment.

Thank you for your help

Thanks I phoned them today and they said my appointment has already been cancelled because my assessor will be off sick - I was told she's phoned in sick this week and they're not allowed to do assessments for a period of time after they're ill because of risk to claimants (they didn't say exactly how long that's for but the upshot is they can't do my assessment next Friday). The woman on the phone had a look to see if I could arrange an appointment while I was on the phone but said there was nothing available and I'll get a letter in the post. I checked that if the new appointment wasn't suitable I could phone to change it and she said yes so that's fine. No idea how long I might be waiting for a new appointment but every week is another week of continued DLA so not complaining.

I recorded the call and noted the date/time of the call on the original letter so if there's any dispute about what was said I have evidence.