% Two asides on one band: a dashboard, not a figure. The second card belongs
% in \stmeaningbox.
\documentclass{standalone}
\usepackage[en]{supertensor}
\stdim{T}{4}
\begin{document}\begin{tikzpicture}
  \strow{R1}{T}
    \stface{A}{}{T}{T}
  \strowend
  \stcallout{N1}{3cm}{R1}{first}{one aside per band}
  \stcallout{N2}{3cm}{R1}{second}{this one has nowhere to go}
  \sttopformula{F}{$A$}
\end{tikzpicture}\end{document}