Pretty sure PR doesn't have internet in most areas after this hurricane.
I think you
can have PR residency and operate remotely from another location.
Your gains prior to moving to PR are still taxed, only future gains are zero. 183 days of residency are required and you cannot have a taxable home (or supported children) living in the mainland anymore. FEMA emergencies do not count against residency for a maximum of two weeks I think.
https://www.irs.gov/pub/irs-pdf/p570.pdf