rebass: "Cannot read property 'rules' of undefined" after upgrading to styled components v4

Seems System.js will generate a styled component without a ‘componentStyle’ attribute in some cases. Having a tough time putting my finger on what could be the solution.

styled-components.browser.esm.js:1736 Uncaught TypeError: Cannot read property 'rules' of undefined
    at createStyledComponent (styled-components.browser.esm.js:1736)
    at templateFunction (styled-components.browser.esm.js:1971)
    at eval (index.js:32)
    at System.create (System.js:117)
    at eval (Box.js:17)
    at Object../node_modules/grid-styled/dist/Box.js (commons.js:2940)
    at __webpack_require__ (commons.js:725)
    at fn (commons.js:102)
    at eval (index.js:7)
    at Object../node_modules/grid-styled/dist/index.js (commons.js:2964)