Not sure if it helps, but I disconnected because my internet went out.
https://paste.dimdev.org/qesapazome.mccrash
--EDIT--
Related crash on a friends game when the server stoppped
https://paste.dimdev.org/bomohugixo.mccrash

First one should be fixed as of BP 0.3.7.5 by a7a5995.
Second one has likely been fixed by now as well. If it's still happening with a more recent version of BP, please post the new crash report (and the game log) for it.