I'd learned 始{はじ}めに to mean "in the beginning" or "firstly" a while back, and recently I came across 初{はじ}めに to have the exact same meaning.
I looked it up on the dictionary, and the two actually appear as alternative spellings for the exact same entry, as opposed to two separate entries with similar meanings.
Is there any nuance to when one should be used over the other; for instance, does the nuance with regards to starting something as it relates to time vs starting a process, as explained in the first part of this answer apply here? Or are they completely interchangeable?