Update: It appears that the new builds are only for the Nexus 5X, 6P, and Nexus 9.
Last week, Google announced the Android N Developer Preview. Major preview versions will come every 4-6 weeks, but the company has just released a small OTA update to devices running Android N.
The updates are less than 30MB in size and Google has yet to post a changelog, but they likely address critical bugs as it was assumed Google would not release any updates in between the previews. Since last week, Googlers have been marking bugs submitted to the Android Issue Tracker as fixed in a future version. Presumably, there were enough fixes to warrant an OTA.
Users can wait for the OTA or flash the factory images if they’re impatient:
If you need help flashing factory images, check out our guide here. Keep in mind that flashing your device will wipe any data on it. For most users, this is not worth the hassle and waiting for the OTA is the wiser option. Google has said that OTAs can take up to 24 hours to show up on a device. This is faster than the usual week long period with other updates.