Builders changed plans without letting me know

Jjboy98

Hello I reserved a new build home off plans in Scotland in June this year I am using shared equity scheme to help buy the house and due to errors with the builders solicitor(not sending the Scottish ministers my postcode so they would not release the funds) I have not concluded my missives. It is a end terrace house and because it is an end terrace on the plans it did not have a shared path for neighbours to access their gardens as they had access from the other side of the terrace. I managed to see into the garden from a friends house to find they have built a path running through my garden that is not on the plans. After talking to the site office they had no idea of the path and where aware it was supposed to be the way I was shown upon further digging the site office found there was a new plan released that they had not seen that involved a path in my garden. Now it might not seem much but my garden was already small as it is and now they have cut 4 foot off the length of my garden without telling me. The site office have told me that this has been put there for access to the gardens that back on to mine Incase of any problems they need to dig up, but I don’t believe it. I am supposed to be moving into my house next month and if I hadn’t looked I would of never known! I have also been told if I’m unhappy there an other house at the other end of the estate that won’t be ready till March next year and is 2.5k more expensive that I can have or I’ve to pull out of the deal and loose my deposit without an apology or even any condolences. The site office still don’t have a copy of the plans. My family has been looking forward to our new home since the start of the home and is our dream home. I’m looking for any advice and who is the best to speak with in this case and where do I stand?
Thanks for your help I’m really stressing out at the moment any help would be great