OS Release Schedule or pulling a dev build

[smashingchrische]

Hello everyone,
I have a question an important feature for me (IPv4 multicast support) has been merged yesterday into the development branch.
I need this feature to enable a range extension for my Homematic devices with a HAP-IP Gateway.
Is there somekind of Release schedule. I would like to know how long I would need to wait until this feature would be available for me.
Is there an option to pull a dev version of the os and update to the next release when it is available?
Thanks in advance, hope I can get some information. I am just starting out with HomeAssistant and decided to use my RPI-3 with a RPI-MOD module for homematic and other automation tasks.