A second signature is required for retroactive payments of up to 2 years, anything beyond that requires a 3rd signature. In the VA literature the 2nd signature is for up to 2 years retroactive OR a dollar amount not to exceed $15,000. For $25,000? A 3 rd signature is required. The other possibility is a rookie rater is working your claim and their mentor has to confirm the voracity of their decision, requiring the second signature. It’s one or the other and VA won’t divulge which, so it’s impossible to say. You can kind of spy on the process and go on VA.GOV and utilize the payments tab. If it’s backpay? You’ll often see a scheduled payment BEFORE you get notified of the decision. Another possibility is, and it doesn’t happen often, is they intend to sever service connection for which you were previously awarded. If your award is under 10 years old they can sever service connection based on an error or fraud. Hope this helps.