Mup - verifying deployment fails - exit status 254!

hello ,
After the recent update of mup, at the verifying stage i am getting this error ,
any idea?

npm ERR! node v4.8.0
npm ERR! npm v3.10.10
npm ERR! code ELIFECYCLE
npm ERR! meteor-dev-bundle@0.0.0 install: node npm-rebuild.js
npm ERR! Exit status 254
npm ERR!
npm ERR! Failed at the meteor-dev-bundle@0.0.0 install script ‘node npm-rebuild.js’.
npm ERR! Make sure you have the latest version of node.js and npm installed.
npm ERR! If you do, this is most likely a problem with the meteor-dev-bundle package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR! node npm-rebuild.js
npm ERR! You can get information on how to open an issue for this project with:
npm ERR! npm bugs meteor-dev-bundle
npm ERR! Or if that isn’t available, you can get their info via:
npm ERR! npm owner ls meteor-dev-bundle
npm ERR! There is likely additional logging output above.

    npm ERR! Please include the following file with any support request:
    npm ERR!     /bundle/bundle/programs/server/npm-debug.log

    => Redeploying previous version of the app

    -----------------------------------STDOUT-----------------------------------

    To see more logs type 'mup logs --tail=50'

    ----------------------------------------------------------------------------

(node:3128) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): Error:
-----------------------------------STDERR-----------------------------------
"
npm ERR! node v4.8.0
npm ERR! npm v3.10.10
npm ERR! code ELIFECYCLE
npm ERR! meteor-dev-bundle@0.0.0 install: node npm-rebuild.js
npm ERR! Exit status 254
npm ERR!
npm ERR! Failed at the meteor-dev-bundle@0.0.0 install script ‘node npm-rebuild.js’.
npm ERR! Make sure you have the latest version of node.js and npm installed.
npm ERR! If you do, this is most likely a problem with the meteor-dev-bundle package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR! node npm-rebuild.js
npm ERR! You can get information on how to open an issue for this project with:
npm ERR! npm bugs meteor-dev-bundle
npm ERR! Or if that isn’t available, you can get their info via:
npm ERR! npm owner ls meteor-dev-bundle
npm ERR! There is likely additional logging output above.

npm ERR! Please include the following file with any support request:
npm ERR! /bundle/bundle/programs/server/npm-debug.log