Spelly,
In an unusual quirk, if Central beat Norwood by about 3 goals (I think, depending on scores) then Central's percentage will still be below Glenelg's and Norwood's percentage will drop below Glenelg.
In this case, Glenelg will rise from 3rd to 2nd whilst having a bye.
Has this ever happened before, where a team rises up the ladder after having a bye?