Here is a proposed release schedule for 0.19.0, the next major release of Bitcoin Core. Like for previous major releases I've aimed for a release 6 months after the last ( #14438).

2019-09-01 ✔️

• Open Transifex translations for 0.19
• Soft translation string freeze (no large or unnecessary string changes until release)
• Finalize and close translations for 0.17

2019-09-15 ✔️

• Feature freeze (bug fixes only until release)
• Translation string freeze (no more source language changes until release)

2019-10-01 ✔️

• Split off 0.19 branch from master
• Start RC cycle, tag and release 0.19.0rc1
• Start merging for 0.20 on master branch

2019-11-03 ✔️

• Release 0.19.0 final (aim)

If any specific dates or timeframes are a problem for you, let me know.

Edit: schedule was moved two months back on 2019-05-07, for reference, the old schedule was:

2019-11-01    Soft translation string freeze
2019-11-15    Feature freeze
2019-12-01    Split off 0.19 branch from master
2020-01-03    Release 0.19.0 final (aim)