Aging vs Bottling - when to make the switch?

I've been brewing a kit of White Zin from ECKraus and everything, so far, has gone by the book. I did my second racking tonight after 25 days. The initial fermentation went great, lots of activity from days 2 through 7. On day 7 I racked and put the wine under an air lock. I kept an eye on the amount of gas escaping the air lock and it stayed pretty constant through day 21 or so. I didn't get to rack it on day 21 like the instructions called for, I waited until day 25. At this point there was zero gas escaping the air lock. The instructions call for another 5 or 6 weeks before I bottle, is this normal or should I bottle it now? The hydrometer reads 0.995 and the instructions said to aim for 0.998. Is the wine done fermenting and is just aging? I've kept the wine at 67-68 degrees Fahrenheit consistently throughout the process.

My first batch so I just don't know what to look for or what to expect. I'm sure the wine is giving me the signals I need, I just don't know how to interpret them!

Thanks for the help!

You don't have to bottle when the instructions tell you. As long as you've racked and have it under airlock it's fine. If you're going to bulk age it for a while, it wouldn't have been a bad idea to add some potassium metabisulfite (also known as campden tablets), but it doesn't sound like you'll be aging it for an extending time period. The instructions suggest adding k-meta when you bottle if you're going to be keeping it a while, and I think that's a good idea.