There is no dilution until the distribution rises significantly. The reason for that is that EVEP pays out more distributions due to the GP additional units on one hand, but on the other hand will not be paying IDRs that it was paying at current distribution levels. For now, the net of those two factors is a wash. At much higher distribution levels, yes, the net will be dilutive but then we will be getting much higher distributions so we will be happy.
P.S. One analysis estimated that the overall impact only becomes negative to current LP unitholders once the distribution has risen 46% from current levels.