Pastors pride 2
I gather that the issue is the temporal sense of the periphrastic ἔσται δεδεμένον/λελυμένον from Matthew 16:19.
I was taught that the voice of the participle determines the voice of the periphrastic construct. Here, δεδεμένον/λελυμένον is in the middle voice, suggesting that the thing being bound/loosed plays a part in its own binding/loosing. The perfect tenseform of the participle has a stative aspect and brings the participle (verb) into the foreground. Porter's "Fundamentals of New Testament Greek" (chapter 28) lists the future equative + perfect participle as equivalent to the future perfect indicative of the participle's finite verb, here "will have been bound/loosed". The temporal sense of the periphrastic construct is future.
Putting these together suggests that the binding/loosing on earth plays a part in the equivalent binding/loosing in heaven, with the 'foreground' emphasis on the thing that happens in heaven and 'background...