I noticed in the latest update that the F-35s have things like "2017, Block 3F, 7G Clearance" and "2025, 6x AMRAAM, Block 3I/4, 9G Clearance", with agility being 4.5 for all F-35 entries up until those "9G Clearance" entries (which are 5.0 for agility).
So firstly, Block 3i was the predecessor to Block 3F (3i = Block 3 initial, 3F = Block 3 Final); Block 3i was first delivered to operational squadrons in 2016, allowing USAF IOC of the F-35A in August 2016. Then, in February 2018, Block 3F was released. Block 3F also saw the F-35B's G limit lifted from 5.5G to 7G. The F-35C's G limit was already at its design max of 7.5G by Block 2B, but the F-35C won't be operational with the Navy until early 2019 anyway.
Then as for flight envelopes, Block 2B / 3i gave the F-35A a 7G flight envelope, Block 3F (again, released in February 2018) gives the F-35A a 9G flight envelope:
Block 4 is a bit messy, as the F-35 program is moving from big block software releases every couple of years, to software releases every 6 months (beginning later this year), but with "Block 4" not beginning until something like 2021 (tl;dr, using 2025 as the date for Block 4 is fine).
You can see the schedule for these 6 month software patches in the "Development" section of the image below - there's the continuous and overlapping development and test phases, and then discrete releases (shown in the row just above the big yellow "FMSim (Dev/Integ/Test)" bar):
So in other words:
In 2015, the F-35B enters USMC service with Block 2B, a 5.5G limit and a Mach 1.2 limit.
In 2016, the F-35A enters USAF service with Block 3i, a 7G limit, 40,000ft limit and a Mach 1.6 limit (F-35Bs also began receiving / upgrading to Block 3i, but this doesn't change their abilities).
In 2017, nothing happens (besides Israel declaring F-35A IOC in December 2017).
In 2018, all 3 variants receive Block 3F in February; the F-35A improves to 9G, the F-35B improves to 7G, the F-35C improves to 7.5G. The F-35B and F-35C get certified to fly at Mach 1.6 in May 2018 and June 2018. All 3 are permitted to fly to 50,000ft (or higher). ***Note that the software only actually limits G limits; pilots can exceed altitude and airspeed limits if they don't mind getting in trouble.***
In late 2018 to (roughly) 2021, there's software upgrades every 6 months, but these are sometimes called 'patches' to Block 3F, correcting outstanding deficiencies and adding things like an Automatic Ground Collision Avoidance System.
In (roughly) 2021 to (roughly) 2026, Block 4 software upgrades are rolled out every 6 months, hardware upgrades are rolled out every 2 years (likely in something like 2022 and 2024), including a Tech Refresh 3 that upgrades the F-35's core processors, etc.
Some of the Block 4 capabilities are shown in the chart below; in total there's meant to be roughly 60 software / hardware upgrades, as well as 30+ weapons being integrated: