If we take all the dates of her posts (if there are some within a 3 day period then take the average date) and work out the pattern formula then we may be able to predict accurately (give or take a couple of days) when she will next appear...
Then again Senesia probably only comes on when she has the time, so that won't work very well.
If you're tlaking about symnzXx, then maybe he's just lonely and is wainting for another female presence on the forum...or maybe he wants to ump her for saying something bad?