Both organizations appear to have added and subtracted class seperation designations over the years(and it most likely continue), the objective is to do what you are doing Don and get the proper answer before the question really NEEDS asked and defined(as Jack referenced).
PS and PB as the second designator are commonly defined between venues. And although SCTA
recognize both, it appears from Dean' explanation that they only
currently authorize the latter, while ECTA only recognizes and authorizes the former.
All
BASE ECTA classes were obtained from the SCTA.
Sometimes differences shown can help
regain unity.
<---(the scrunchy face is correct)
Todd