Apparently, while it is impossible to read signatures, since the bounty lasts until December 8.

"We also announce that, on November 21st 2018, a second phase of the Airdrop (the last one) will begin, which will last along with the Bounty campaign, until December 8th 2018, the official closing date of the Public Sale."

Read this article: https://medium.com/@BitSongOfficial/important-bitsongs-public-sale-notice-e70e448bd90c