  In the upcoming LHC Run 2, at $\sqrt{s} \sim13$ TeV, it is suggested to seek
unusually charged ($Q= -4/3$ and $+5/3$) quarks with mass $M_Q \sim 3$ TeV
which carry lepton number ($L = +2$ and $-2$ respectively) and decay
superweakly to a bilepton $Y$ with mass $M_Y\sim2.5$ TeV and a usual quark.
These long-lived decays will have displaced decay vertices and produce a
striking final state in $pp$ which contains two separated jets together with
two pairs of correlated like-sign charged leptons. Such a process was
inaccessible energetically in LHC Run 1 with $\sqrt{s} \sim8$ TeV. The simplest
theoretical explanation is the 331-model which has new physics necessarily
below $4$ TeV and which explains the existence of three families by anomaly
cancellation.
