“(1) Liability to a penalty under any paragraph of this Schedule does not arise in relation to a failure to make a payment if P satisfies HMRC or (on appeal) the First-tier Tribunal or Upper Tribunal that there is a reasonable excuse for the failure. (2)For the purposes of sub-paragraph (1)— (a) an insufficiency of funds is not a reasonable excuse unless attributable to events outside P's control, (b)where P relies on any other person to do anything, that is not a reasonable excuse unless P took reasonable care to avoid the failure, and (c) where P had a reasonable excuse for the failure but the excuse has ceased, P is to be treated as having continued to have the excuse if the failure is remedied without unreasonable delay after the excuse ceased”