depends... You can get a 1060 for under 300 bucks new ... to hold you over. yeah, a 1060, may not play all the games you want at certain levels, but it will let you play games decently for the time being. Then when and IF they come out with a new card(s).... You can sell they 1060 for 100~200 (whatever you can get for it) and buy what you really wanted.
Tho, one question you gotta ask yourself.... Do you think when the new 11XX flavor comes out, will it be the card you want? What do I mean by that? Normally, companies will design the lower end card first and then step up to the faster cards, and then a few months later bring the best card (fastest memory and clock speeds) out. Would royally suck, if you waited and spent your wad on something new just to realize you should have waited for the best of the 11XX flavors to come a few months longer. Just like when the 1080 came out, the 1080ti came out a bit later and was the card most people wanted.
I'm thinking most people think that by end of August we'll see a new card, (that's what people want) ... But in reality, I think by 4Q 2018 we'll see that possibility come to life. Nvidia isn't stupid and most gamers are going to want the new flavor for Xmas. Then again, maybe the new flavor will come out by 3Q and the grand daddy TI to come out in the 4th Q. Time will tell!

By then, if you haven't made up your mind to sell your used 1080ti... Be lucky to get 2~300 bucks for them.
Moral of the story, don't miss the boat to get the best dollar for your used hardware. As that opportunity doesn't stay open for long!