Can a response to office action be amended?

[Art1]

I filed a response to an office action 30 days after the 3 months limit and paid the appropriate extension of time fee. The response to office action have not yet been examined and I would like to amend it. I have couple questions:
1. Is there a special form or should I simply use the same format as replying to an office action and just indicate in the heading that this is an amendment to the office action dated xx/xx/2019
2. Do I have to pay another extension of time fee for another month as the amendment will be filed after the last day of the 30 days extension of time already paid.

[bluerogue]

I filed a response to an office action 30 days after the 3 months limit and paid the appropriate extension of time fee. The response to office action have not yet been examined and I would like to amend it. I have couple questions:
1. Is there a special form or should I simply use the same format as replying to an office action and just indicate in the heading that this is an amendment to the office action dated xx/xx/2019
2. Do I have to pay another extension of time fee for another month as the amendment will be filed after the last day of the 30 days extension of time already paid.

1. No. Just reply as you normally would.
2. No. You have already replied.

You should also be aware that your supplemental reply may not be entered.  It is at the discretion of the examiner.  I will normally enter these if I haven't picked up the file, but you don't know if the examiner has already looked at the amendment or not.

MPEP 714.02

(i) A reply that is supplemental to a reply that is in compliance with § 1.111(b) will not be entered as a matter of right except as provided in paragraph (a)(2)(ii) of this section. The Office may enter a supplemental reply if the supplemental reply is clearly limited to:

    (A) Cancellation of a claim(s);
    (B) Adoption of the examiner suggestion(s);
    (C) Placement of the application in condition for allowance;
    (D) Reply to an Office requirement made after the first reply was filed;
    (E) Correction of informalities (e.g., typographical errors); or
    (F) Simplification of issues for appeal.

[Art1]

Thanks for the advice. I contacted examiner and she agreed to enter the amendment. Thank you.