Comment (by Roland Haas):

I had not even realized you had provided a plot (only looked at the email notification). Hmm, will have to see where the offset comes from. Physically it does not matter of course since it is just a time offset but the code was originally designed to reproduced SimulationTools results as much as possible.

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2413/include-power-code-to-extrapolate