STT:
I think we agreed that once time exist then it doesn’t need a sustainer.
Mmmmm… not particularly. Sustainer in the sense that it needs an outside factor to operate in change and fulfill its inner most attributes? Well then no, it does not need one. Sustainer in the sense that without some entity ontologically prior to its existence it would have no eternal being (like a camper continually supplying wood to a fire)? In that case, yes, it does need a sustainer.
Moreover, we agreed that time cannot be created
Yes, in the sense that it does not begin to exist. That does not, however, properly explain why it exists at all. If something is of a given manner, say eternal or temporal, it is not beyond the bounds of reasonable question to ask why they are so.
So the conclusion is time is not contingent.
We should be careful in knowing our terms here, STT. For if contingency is whether or not something is temporal or eternal, then certainly the the temporal framework is noncontingent. If, however, it is whether or not an entities being is explained by external factors and not merely internal factors, then the eternality of the subject isn’t as relevant as we may be led to believe.
I hold myself firmly to the ladder determining of contigency over the former. If that be so, we therefore must ask how we may determine whether or not an entity is soley under the influence of internalities, or if externalities play a role in it. The best way to discover such is be asking whether or not a being changes, for if it did change in any way, then it maybe influenced by what is beyond merely itself, and thus we may deduce its contigency. The other factor, as I’ve argued before, is finitude and infinitude. And because time is both finite (in so far as we know) and can most definitely change, it therefore follows that time is contingent.
There was either nothing or something at the beginning of time.
Well yes, time itself. It doesn’t follow from such that anything else was there though other than the thing which may sustain time.