Formal Charges still to come
Might takes months and months to know the exact charges.
(It's not like committing a crime, where you are charged upon arrest)
Even if the aircraft sustained only minor damage, this still should qualify as an accident due to the cost to repair the damaged power lines. Although the pilot must immediately notify the NTSB, they actually have 10 days to complete a more formal wriiten report.
I would expect that the phone notification included just the minimum details, and may have even be made by the company and not the pilot involved.
After the NTSB gets notified, they'll contact the local FAA Office.
The pilot will then get a phone call from the FAA. Since no one was hurt, they may wait for the filing of the written report before further follow-up with the pilot. The pilot may also choose not to discuss anything with them until securing legal representation.
And there are even more ways this could go.
Like anything involving the Govt. it usually moves slowly.