Yes. Having an alternate supplier does not affect RRES eligibility.
For an RRES project participating in the Netting incentive structure, any excess production would be credited at the Eversource retail rate (not the supplier rate), while any excess consumption would be charged at the alternate supplier rate.
For an RRES project participating in the Buy-All incentive structure, your account will be billed normally at the supplier's rate and any on-bill credits would be applied at the Buy-All incentive rate.