The port authority may establish a certain fashion of operation based on the bylaws that are in place now in the neighbouring municipality or jurisdiction and then all of a sudden, if that jurisdiction were to change its bylaws, it could cause the port authority to have to make substantial and profound changes in the way it operates.
The port authority's operations are currently tied to the neighboring city
Though we know that the port authority may change its laws to match those of the neighboring area, we do not know if the two are currently tied. That information is outside this context. The system may have assumed from the context that the two are already tied. 
( z1 tie :ARG1 ( z2 operate :ARG0 ( z3 authority :mod ( z4 port ) ) ) :ARG2 ( z5 city :ARG1-of ( z6 neighbor ) ) :time ( z7 current ) )