With no biological filter, keep the fish load small and you should be okay. That said, fish are really the pickiest about cycle times. It's hard to fully break the six week rule on nitrogen cycle bacteria, whatever you do, but plants are usually okay to go in the first week. I don't have any use for commercial bacteria products because I find ponds have to self-balance either way, but I won't gainsay anyone who reports different experiences with them.
I like to take it slow with a new pond making small additions over time as I learn the patterns, but it's hard to overdo plants if you're willing to take them out or thin later if needed. On the other hand, a lot of newly potted plants can bring extra nutrients with them since the soil hasn't been fully locked down and colonized.
I can't tell you whether to wait or not. You will save yourself winterizing and spring cleaning if you wait, but that excuse could be used every year to never start a pond. I don't know where your plants are coming from--some are better divided in the spring. I guess if it were me, I'd fill it up, get familiar with it, and then decide come freezing weather whether to drain it and cover it for a new startup in spring, or keep it filled through its first winter.
