Resumable File Upload

[garrett-wombat]

Im trying to figure out if i can use the storage uploadBytesResumable to restart an upload of an upload that was started previously. The ref will be same same, the file will have the exact same bytes. Will this utility restart the upload overriding the bytes already stored, or will it resume. Alternatively is there a way to initialize this upload from the offset of bytes i already know has been completed? I think theres a header that defines the range of bytes being uploaded.

If theres another way to do this (resume an upload through a refresh or application crashing) please set me know.