diff --git a/packages/@uppy/transloadit/lib/index.js b/packages/@uppy/transloadit/lib/index.js
index 58d2664..44cb86d 100644
--- a/packages/@uppy/transloadit/lib/index.js
+++ b/packages/@uppy/transloadit/lib/index.js
@@ -223,17 +223,18 @@ export default class Transloadit extends BasePlugin {
           );
           _classPrivateFieldLooseBase(this, _connectAssembly)[_connectAssembly](this.assembly);
         };
-        const updateAssemblies = () => {
+        const updateAssembly = () => {
           var _this$assembly;
           return (_this$assembly = this.assembly) == null ? void 0 : _this$assembly.update();
         };
-        this.restored = Promise.resolve().then(() => {
+        this.restored = (async () => {
           restoreState();
           restoreAssemblies();
-          updateAssemblies();
-        });
-        this.restored.then(() => {
+          await updateAssembly();
           this.restored = null;
+        })();
+        this.restored.catch(err => {
+          this.uppy.log("Failed to restore", err);
         });
       },
     });
@@ -251,6 +252,7 @@ export default class Transloadit extends BasePlugin {
           const assembly = (_this$assembly2 = this.assembly) != null
             ? _this$assembly2
             : await _classPrivateFieldLooseBase(this, _createAssembly)[_createAssembly](fileIDs, assemblyOptions);
+          if (assembly == null) throw new Error("All files were canceled after assembly was created");
           if (this.opts.importFromUploadURLs) {
             await _classPrivateFieldLooseBase(this, _reserveFiles)[_reserveFiles](assembly, fileIDs);
           }
@@ -274,46 +276,41 @@ export default class Transloadit extends BasePlugin {
     });
     Object.defineProperty(this, _afterUpload, {
       writable: true,
-      value: (fileIDs, uploadID) => {
-        var _this$assembly3;
-        const files = fileIDs.map(fileID => this.uppy.getFile(fileID));
-        const filteredFileIDs = files.filter(file => !file.error).map(file => file.id);
-        if (this.restored) {
-          return this.restored.then(() => {
-            return _classPrivateFieldLooseBase(this, _afterUpload)[_afterUpload](filteredFileIDs, uploadID);
-          });
-        }
-        const assemblyID = (_this$assembly3 = this.assembly) == null ? void 0 : _this$assembly3.status.assembly_id;
-        const closeSocketConnections = () => {
-          var _this$assembly4;
-          (_this$assembly4 = this.assembly) == null || _this$assembly4.close();
-        };
-        if (!_classPrivateFieldLooseBase(this, _shouldWaitAfterUpload)[_shouldWaitAfterUpload]()) {
-          var _this$assembly5;
-          closeSocketConnections();
-          const status = (_this$assembly5 = this.assembly) == null ? void 0 : _this$assembly5.status;
-          if (status != null) {
+      value: async (fileIDs, uploadID) => {
+        try {
+          var _this$assembly3, _this$assembly6;
+          await this.restored;
+          const files = fileIDs.map(fileID => this.uppy.getFile(fileID)).filter(file => !file.error);
+          const assemblyID = (_this$assembly3 = this.assembly) == null ? void 0 : _this$assembly3.status.assembly_id;
+          const closeSocketConnections = () => {
+            var _this$assembly4;
+            (_this$assembly4 = this.assembly) == null || _this$assembly4.close();
+          };
+          if (!_classPrivateFieldLooseBase(this, _shouldWaitAfterUpload)[_shouldWaitAfterUpload]()) {
+            var _this$assembly5;
+            closeSocketConnections();
+            const status = (_this$assembly5 = this.assembly) == null ? void 0 : _this$assembly5.status;
+            if (status != null) {
+              this.uppy.addResultData(uploadID, {
+                transloadit: [status],
+              });
+            }
+            return;
+          }
+          if (!assemblyID) {
             this.uppy.addResultData(uploadID, {
-              transloadit: [status],
+              transloadit: [],
             });
+            return;
           }
-          return Promise.resolve();
-        }
-        if (!assemblyID) {
-          this.uppy.addResultData(uploadID, {
-            transloadit: [],
-          });
-          return Promise.resolve();
-        }
-        const incompleteFiles = files.filter(file => !hasProperty(this.completedFiles, file.id));
-        incompleteFiles.forEach(file => {
-          this.uppy.emit("postprocess-progress", file, {
-            mode: "indeterminate",
-            message: this.i18n("encoding"),
+          const incompleteFiles = files.filter(file => !hasProperty(this.completedFiles, file.id));
+          incompleteFiles.forEach(file => {
+            this.uppy.emit("postprocess-progress", file, {
+              mode: "indeterminate",
+              message: this.i18n("encoding"),
+            });
           });
-        });
-        return _classPrivateFieldLooseBase(this, _watcher)[_watcher].promise.then(() => {
-          var _this$assembly6;
+          await _classPrivateFieldLooseBase(this, _watcher)[_watcher].promise;
           closeSocketConnections();
           const status = (_this$assembly6 = this.assembly) == null ? void 0 : _this$assembly6.status;
           if (status != null) {
@@ -321,7 +318,9 @@ export default class Transloadit extends BasePlugin {
               transloadit: [status],
             });
           }
-        });
+        } finally {
+          this.assembly = undefined;
+        }
       },
     });
     Object.defineProperty(this, _closeAssemblyIfExists, {
@@ -507,12 +506,13 @@ function _attachAssemblyMetadata2(file, status) {
   }
   return newFile;
 }
-function _createAssembly2(fileIDs, assemblyOptions) {
+async function _createAssembly2(fileIDs, assemblyOptions) {
   this.uppy.log("[Transloadit] Create Assembly");
-  return this.client.createAssembly({
-    ...assemblyOptions,
-    expectedFiles: fileIDs.length,
-  }).then(async newAssembly => {
+  try {
+    const newAssembly = await this.client.createAssembly({
+      ...assemblyOptions,
+      expectedFiles: fileIDs.length,
+    });
     const files = this.uppy.getFiles().filter(_ref => {
       let {
         id,
@@ -544,7 +544,7 @@ function _createAssembly2(fileIDs, assemblyOptions) {
     this.uppy.emit("transloadit:assembly-created", status, fileIDs);
     this.uppy.log(`[Transloadit] Created Assembly ${assemblyID}`);
     return assembly;
-  }).catch(err => {
+  } catch (err) {
     const wrapped = new ErrorWithCause(`${this.i18n("creatingAssemblyFailed")}: ${err.message}`, {
       cause: err,
     });
@@ -555,7 +555,7 @@ function _createAssembly2(fileIDs, assemblyOptions) {
       wrapped.assembly = err.assembly;
     }
     throw wrapped;
-  });
+  }
 }
 function _createAssemblyWatcher2(idOrArrayOfIds) {
   const ids = Array.isArray(idOrArrayOfIds) ? idOrArrayOfIds : [idOrArrayOfIds];
@@ -655,6 +655,7 @@ function _onAssemblyFinished2(assembly) {
 async function _cancelAssembly2(assembly) {
   await this.client.cancelAssembly(assembly);
   this.uppy.emit("transloadit:assembly-cancelled", assembly);
+  this.assembly = undefined;
 }
 function _connectAssembly2(assembly) {
   const {