Income related ESA

I am on contribution based ESA in the support group. I am filling out an esa3 form to see if I can claim income related. There are a few things in the form I'm unsure on and I would be very grateful if someone could help me.

1) In 'Part 6: About other benefits' under 'Benefit 1' I have filled in the details of my PIP. Under 'Benefit 2' do I need to fill in details of my current contributions based ESA?

2) When I send back my completed esa3 form I need to enclose a bank statement, does it have to be an original or can I send a photocopy of my bank statement?

3) I am also filling in an is10 form. Do I need to wait to hear back about the outcome of my esa3 form first? Or can I send the is10 at the same time as the esa3?

Thank you Gordon.

I have some more questions if you don't mind helping me again.

1) In 'Part 4: About your disability' there is a question that asks "Name of the doctor who signs your Statements of Fitness for Work 'Statements of Fitness for Work' are also called fit notes, medical certificates, doctors's statements or sick notes." and "Address of the doctor who signs your Statements of Fitness for Work" - Do I need to fill these in? I no longer have to provide sick notes as I am in the support group, it's been some time since I last had to provide sick notes and the doctor that used to sign my sick notes has retired and I have a new doctor.

2) In 'Part 6: About other benefits' The question "Does anyone care for you on a regular basis?" - What is classed as a regular basis?
It then asks for the person's name and address and if they get Carer's Allowance for caring for me.

After sending in the ESA3 form and then some extra information I received a decision letter about ESA IR arrears (from when I transferred from Incapacity Benefit to ESA CB) a couple of weeks ago. The letter says the amount of arrears I will receive and states: By law we are unable to pay you for any period before 21st October 2014 (Section 27 of the Social Security Act 1998).

I would like to submit a Mandatory Reconsideration about the 21st October 2014 date, but I am not sure how long I have to do it because the decision letter has no date written at the top right. The letter also has no address or phone number to contact them on. This is what's written on the top right of the decision letter:
[Building /Office Location]
[Office Type]
[Street]
[Town]
[County]
[Postcode]

[Telephone 0000 000 0000]
[Textphone 0000 000 0000]

Please read this letter in full. If you need more information about this letter or need it in Braille, large print or audio please call us on 0000 000 0000.

It looks like the person who wrote/sent out the letter forgot to fill in the address and phone number.

I have a few questions regarding the mandatory reconsideration and would really appreciate some help.

1) When the DWP have made a decision on something, how long do you have to do a Mandatory Reconsideration? Is it 4 weeks? Or is it 1 calendar month?

2) If the decision letter doesn't have a date written on it, would the 1 month time limit still apply?

3) I can imagine my Mandatory Reconsideration will result in the same as my decision letter and they will stick with their decision to not pay arrears prior to 21st October 2014, so then I will go to appeal. If such an appeal is lost, will it have any negative affect for me with the upcoming court case between CPAG and DWP? For example if the DWP lose and then have to repay the arrears owed prior to 21st October 2014, I am worried that if I lose my appeal it will mean that I won't be able to try and claim the extra arrears. So I am wondering if maybe I should just leave it and not go ahead with a Mandatory Reconsideration/appeal and instead just wait it out and see what happens with the CPAG DWP case?