A state trust company may merge with another trust company or into a depository institution pursuant to the applicable provisions of part 13 of this chapter, or as otherwise permitted. However, any requirement that an institution must be in operation for three (3) years before engaging in a merger transaction shall not apply to trust companies. Mergers of state trust companies into a resulting out-of-state trust institution is permitted to the same extent that the other state's law permits Tennessee trust institutions to merge with trust companies of the other state. If a state trust company merges into an out-of-state trust institution, the resulting out-of-state trust institution may operate a trust office at the location of the state trust company pursuant to the notice requirements for the offices under this chapter, but the office shall not constitute a branch.