v0.21.1

What's Changed

• Remove superfluous next_flush by @janbjorge in #365
• Remove use of rich object time object in pop_until by @janbjorge in #366
• Adjust default buffer flush timeout to 100ms by @janbjorge in #367
• Halve heartbeat buffer timeout and use full retry interval for execut or heartbeats by @janbjorge in #368

Full Changelog: v0.21.0...v0.21.1

Thanks to tindzk for reporting #364 and assisting with #367