Builder purposely slowing down progress to get out of contract

[Austin Jones]

I'm trying really hard to not put on my tin foil hat, but here's the situation:
We are under contract for a lake house in a VERY hot market (Lake Hartwell, SC/GA).  Houses are listed, immediately a multiple offer situation occurs, and are under contract over ask.  It's wild, and we missed on a few deals before finally getting under contract.  It was weird when it happened because the house was listed in the middle of construction but would be sold completed.  No big deal, in this market we were hopeful this may drive a few offers away and up our chances.

We got under contract and construction progress is REALLY slow.  I'm legit concerned that it won't be done before the close date.  Normally I wouldn't really care, except I have this sneaky suspicion that builder (who is also the seller) is slow walking this to get it to fall through.  Important construction tasks are not being done, vacations being taken, documents not being provided that are normal and I need for my lender and stonewalling my agent.  My agent informed me that our property is probably up 10% from what we're under contract for a month ago and we have a over a month to go until closing.  She said it's not unheard of for less-than-reputable agents to use this as almost a hedge in rapidly increasing markets.  Essentially get under contract in a hot market during construction of a spec property, and if the market keeps accelerating do something to get out of the contract and be able to re-list when the property is complete assuming a greater price.  Flip side, if the market cools off you've already go your contract in place. 

I feel like a crazy conspiracy theorist here.  I'm typically pretty even keel and this is certainly not my first real estate deal.  The whole thing has felt "off" from the start but I chalked it up to listing agents being lazy as hell when houses are flying off the shelf instantly.  

So the questions are: 
1) Is this a real strategy or is my imagination just running wild.  It's pretty genius.  It's a real a-hole move, but its genius I'll admit.  
2) Do I have ANY legal recourse if this happens?  I obviously would get my earnest money back, but we've been dropping cash on other things along the way (dock, furniture, etc) in order to be able to use this property as soon as we close.  What in the world do I do with a dock an no lakehouse haha?  

Thanks!