将时间月份格式化为大写字母

I want to format time to

2006/JAN/hello02JAN2006file.csv.zip

It contains month name in Capital letter,

say downloadDate is time.Time

downloadDate.Format("2006/JAN/hello02JAN2006file.csv.zip") won't convert JAN to Month name, as it won't parse JAN, it will need Jan ,If I give it Jan , then month name will also be like this ( Apr, May, ...) while I need APR or MAY

my solution to work around here is to replace JAN by using strings.Replace method

strings.Replace(downloadDate.Format("2006/JAN/hello02JAN2006file.csv.zip"), "JAN", strings.ToUpper(downloadDate.Format("Jan")), -1)

am I missing something in time.Time doc, or above is the only way to accomplish this ?