Extend simulation without a checkpoint file

GROMACS version: 2018.3
GROMACS modification: Yes/No
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Is it possible to extend a simulation without a checkpoint file using only result files (.trr and .edr, xvg. etc) ?
I know this used to be an option with older versions of convert-tpr but for some reason deprecated. I wonder if there is a replacement for this function?

grompp can do this for you. Set init_step correctly and the continuation option to yes.