Nope.
After downgrading to 8.0, you will receive the normal prompt to upgrade, but ONLY if Cyan is available for your country/carrier. If it is, you will then receive WP8.1+Cyan.
Enrolling in the dev preview afterwards would allow you to get WP8.1.1
Consider also that MS has just released an updated official WP8.1 that correctly allows dev preview devices to correctly update to WP8.1+Cyan. This has already been released in some places.