There was a small question on which I could not find the answer by search. What is an acceptable date range for letters of recommendation/of support? If the letter was written a month ago? What if six months?
There was no provision for dates in the guide but i think a letter written three months before your application should be fine. Some people take up to three months to prepare their supporting documents.
I don’t think the age of the letter matters really. I think I have heard a case of one of the folks who used a letter that is about 6 months old for their second application attempt after getting rejected the first time.
As long as the letter meets the criteria written on the visa guide, you will be fine. I also believe “Be about your Global Talent application - you cannot use a letter that was written for another reason” is a serious criterion.
Also, technation did not say anything about the age of the letter too so you should be safe.