Ambassador, British Airways; FlyerTalk Posting Legend
Join Date: Apr 2012
Location: Leeds, UK
Programs: BA GGL/CCR, GfL, HH Diamond
Posts: 42,971
For reference, BA/AY short haul + TPs are:
Economy (Discounted) - 20 TP per leg
K M L V S N Q O G
Economy (Full fare) - 40 TP per leg
Y B H
Business -80 TP per leg
J C D R I
So your booking of S one way and B the other gives 20+40= 60 TPs as now showing on MMB. If it were G + G you would get 40 TPs in total instead.