HM Government of Gibraltar have recently published an important technical notice with guidance for financial services operators in the event of a No Deal Brexit.
This includes the status of Gibraltar under EU Law as well as the various steps and precautions which the government are taking to minimise disruption to Gibraltar's financial services sector. You can read the document in full here: https://www.gibraltar.gov.gi/new/sites/default/files/press/2019/Press%20Releases/187-2019.pdf
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.