per the release notes, I’m suspecting they’re working on the “access to play” bugs/crashes with minimal content adjustments.
the 2020 development cycle for a Sim Update ended up at about 2+ months, beta testing sometimes found issues to polish and often added a few more weeks.
as a rough guess (and regular business days), 1-1.5 weeks to plan what to update, 3-4 weeks to code, 2-3 weeks for QA testing (which ramps up during primary coding, i.e. learn and design testing for current plan) and implement code fixes per QA testing, 1-2 weeks beta test release, 1-2 days decide & determine release candidate status; 1-2 days roll-up changes into main release, issue client update to production systems. Maybe more time to coding & a little less to QA when they have the tests lined up and just need to add new tests (time could shift depending how intense the update is).
That’s already a 7-11 weeks schedule, around 2-3 months, but the planning could overlap during the QA & beta testing as the code teams wouldn’t be involved - that can pull it back to about 9 weeks. And coding any specific issue that’s a massive area could take longer, e.g. helicopters & gliders as they introduced all new systems.
And, the monthly public overview meetings go over the current bugs list sorted by vote order. This equates into planning future releases. So, this is the chance for the community to voice and vote for the highest concerns for the dev team to address (like the top 25-30).