What I'm saying is that, because he did not contest PL racing in 2015, Seb returned to an average assesed (by whatever formula) as 7.37 The same is true for Charlie Gjedde (ha!) at Plymouth and indeed Henning Bager.
This has kept Seb on that average in May because he had not raced 4 home, 4 away official matches before the cut-off date of April 20th.
Thus, while everyone else's average changed slightly from May 1st, (and will change again on June 1st) Seb's is pegged at 7.37 until seven days after his 4th away match on May 28th, weather permitting.
By which time he will have achieved a 'proper' average again -- which may (or may not) advance him to No 1.