You are right that in a year or two she will be replaced, however, the newcomers are not guaranteed to be more succesful than Serafima. Out of four very tallented ladies that were Serafima's age group (Proklova, Sotskova, Medvedeva, Sakhanovich), only two are currently doing well. Serafima struggles and Proklova seems to be gone. There is a number of ladies that will be newly senior eligible, but half of them may not survive the transition to seniors. Plus from established seniors some of them are also not doing that great. Adelina seems to be lacking motivation, Liza is up and down (and more often down), Julia is currently injured, we haven't seen Elena competing yet this season so it is hard to say, Leonova is not doing any better than Serafima.... so from current seniors Evgenia and Anna seem to be doing fine, possibly also Elena, but it is not as if seniors were overcrowded with ladies who are all currently delivering. There are perhaps three that are delivering, a few that were delivering a year or two years ago, but it is not possible to foresee which ladies will be delivering in a year or two.