submit to appstore from unity 5.2.4

Hello,
I am using unity3d 5.2.4. Around half year ago I upload application to apstore. Now i need to update that application. But I cant, because apple say that i need xcode 8 for submit. To use xcode 8 i need unity3d 5.4 and higher, but i can not do this update because this update wil cause to me a crazy work (I have several thousands of bundles with lightmapdata in it all this data made during year in unity 5.2). Is there any way that i can upload my app using older xcode/unity3d 5.2.x?