Missing main.css files for fullcalendar Angular 11

Question

I have recently updated a project that leveraged angular fullcalendar

I have had a difficult time trying to make this work and am receiving an error that is difficult to follow

Build at: 2021-02-16T06:08:24.802Z - Hash: 2de4aee8b4106ac0f4ba - Time: 30741ms

Error: ./node_modules/@fullcalendar/daygrid/main.css
Module build failed (from ./node_modules/@angular-devkit/build-angular/node_modules/postcss-loader/dist/cjs.js):
Error: EISDIR: illegal operation on a directory, read

Error: ./node_modules/@fullcalendar/timegrid/main.css
Module build failed (from ./node_modules/@angular-devkit/build-angular/node_modules/postcss-loader/dist/cjs.js):
Error: EISDIR: illegal operation on a directory, read

Error: ./node_modules/@fullcalendar/common/main.css
Module build failed (from ./node_modules/@angular-devkit/build-angular/node_modules/postcss-loader/dist/cjs.js):
Error: EISDIR: illegal operation on a directory, read

I have followed the documentation to the best of my knowledge in the context of implementing this into Angular 11x.x and am seeking help in trying to get this to work, not sure what im doing wrong here or what config is bad

Angular CLI: 11.2.0
Node: 15.5.1
OS: linux x64

Angular: 12.0.0-next.0
... animations, common, core, forms, platform-browser
... platform-browser-dynamic, platform-server, router
Ivy Workspace: Yes

Package                         Version
---------------------------------------------------------
@angular-devkit/architect       0.1102.0
@angular-devkit/build-angular   0.1102.0
@angular-devkit/core            11.2.0
@angular-devkit/schematics      11.2.0
@angular/cdk                    11.2.0
@angular/cli                    11.2.0
@angular/compiler               11.2.0
@angular/compiler-cli           11.2.0
@angular/flex-layout            11.0.0-beta.33
@angular/http                   6.1.10
@angular/language-service       11.2.0
@angular/material               11.2.0
@schematics/angular             11.2.0
@schematics/update              0.1102.0
ng-packagr                      11.2.1
rxjs                            6.6.3
typescript                      4.1.5
webpack                         4.46.0

Package.json fullcalendar contents

"@fullcalendar/angular": "~5.3.0",
"@fullcalendar/core": "~5.3.0",
"@fullcalendar/daygrid": "~5.3.0",
"@fullcalendar/interaction": "~5.3.0",
"@fullcalendar/list": "~5.3.0",
"@fullcalendar/timegrid": "~5.3.0",

I have tried

• deleting and installing the node packages
• adding the css resource paths that it cant find in the angular.json
• playing with fullcalendar versions
• double reading docs
• adding the css resource paths in the component scss files as an import"@xxx"