As an exclusive feature of a non-Hermitian system, the existence of exceptional points (EPs) depends not only on the details of the Hamiltonian but also on the particle-number filling and the particle statistics. In this paper, we study many-particle EPs in a Bose-Hubbard chain with two end-site resonant imaginary potentials. Starting from a single-particle coalescing eigenstate, we construct $n$-particle condensate eigenstates for the cases with zero and infinite $U$. Compared with the free bosonic case, where the $n$-particle condensate eigenstate is an ${(n+1)}^{\mathrm{th}}$-order coalescing state, the hard-core boson counterpart is a second-order coalescing state for odd $n$, while it is not for even $n$. The difference in particle-number parity results in distinct quenching dynamics of the condensate states, highlighting the role of parity in system behavior. Our finding may stimulate research on the dynamic sensitivity to particle-number parity.

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• PT-symmetric quantum mechanics
• Quantum quench
• Bose-Einstein condensates
• Exceptional points
• Bose-Hubbard model
• Exact solutions for many-body systems