A year ago, I queried for a manuscript and got several full requests. They were all rejected with the primary reason being the opening was too slow, and various other style quirks as well (1), but most of these agents did request to see future projects (2). I've spent the past year revising the novel and it turned into a completely different novel, with the exceptions of character names and some character personalities, as well as a specific setting and half the title (3). Altogether, the plot is 90% new (and I did rewrite the entire thing), but in a query, there would be parts that would ring bells for agents who have already received a query on the previous version of this work.
I know in one of your recent blog posts you said that no means no. But since a few of these agents did love the premise & writing style, can I still query them with the new, different version of this project? And if I do, should I mention that I've queried a different version of this previously?
Now, here's why I said no.
First, look up where I marked (1). You got rejections saying "the opening was too slow" etc. That is NOT a complete list of why they didn't pounce on your novel with all four fins.
It's what they told you. It's not necessarily the COMPLETE reason.
What they did say clearly is FUTURE projects. (2)
That means something not-this.
You've painted and plastered, and replaced the fixtures, but this house is still at the same address.(3)
I know you want to start with the agents who expressed interest in your work, but you're better off shopping this to fresh eyes.
I've gotten a couple of these refurbished fulls, and I don't think I've ever said yes on the second go-round.
If you elect to ignore this advice, you should mention that you queried before, took their advice to heart and rewrote the novel completely. The part about taking their advice is the key here.