I think it is pretty clear that the writer of the note is educated (knows how to spell difficult words, uses punctuation correctly, uses grammar correctly, uses somewhat outdated terms such as "attache case" correctly, and even uses archaic grammar correctly "and hence") and is simply making deliberate spelling errors etc.
In addition, the note seems stilted and overly formal in some areas. This style could indicate that the writer is foreign as language instructors and textbooks often use slightly archaic and overly formal teaching material.
Or, the style could indicate a native speaker who has received formal training or instruction in writing etiquette. Such training would probably also use formal teaching material and develop slightly archaic language usage. Patsy was arguably southern and may have received writing etiquette classes in the course of pageant competitions.
In addition, the note seems stilted and overly formal in some areas. This style could indicate that the writer is foreign as language instructors and textbooks often use slightly archaic and overly formal teaching material.
Or, the style could indicate a native speaker who has received formal training or instruction in writing etiquette. Such training would probably also use formal teaching material and develop slightly archaic language usage. Patsy was arguably southern and may have received writing etiquette classes in the course of pageant competitions.